1.6.11 (2019-05-23)

        * Changed the bootstrap shebang from sh to bash to address a
          bashism that arrived at 1.6.10.

1.6.10 (2019-05-02)

        * Added additional up-front checks to the bootstrap script to
          ensure required executables are available.

1.6.9 (2019-04-30)

        * Now that both automake and pure make headers and footers are
          co-mingled, address an issues in which the .DEFAULT_GOAL
          specifications in the repos.mak footer were conflicting with
          makefiles that wanted a different default goal by moving
          those .DEFAULT_GOAL specifications to Makefile-bootstrap.

1.6.8 (2019-04-29)

        * Downgraded m4 from 1.4.17 to 1.4.5 since 1.4.5 seems to be the
          last version of m4 that does not abort on invocation in the m4
          *rintf and friends compatibility and portability library.

        * Leverage both automake and pure make headers and footers by
          including the latter in the former.

        * Reworked how verbose progress is handled to simplify
          specification of progress macros.

        * Rebased several automake header macros implementations on their
          pure make equivalents.

1.6.7 (2019-04-26)

        * Addressed issues with NL_FILTERED_CANONICAL in which the desired
          content to be filtered was not filtering correctly and in which
          the desired filtered canonical variables were not emitted in
          makefiles.

1.6.6 (2019-04-09)

        * Added code coverage support for clang, which uses a link flag
          --coverage instead of linking to a library(-lgov) as gcc does
          for code coverage functions.

1.6.5 (2018-11-19)

        * Addressed an issue in which the failure to make the 'repos-warning'
          target order-only caused dependent repo paths to be repeatedly
          and unnecessarily remade which, in turn, caused git operations
          and the configuration or build to fail.

1.6.4 (2018-11-14)

        * Added support for pulling down remote package dependencies using
          git clone (default) or git submodule depending on the setting of
          pull.method in repos.conf.

1.6.3 (2018-10-19)

        * Added support for coverage-local and check-local targets. Added
          documentation for all coverage-related targets.

1.6.2 (2018-10-09)

        * Take a different approach to version flapping against 'make
          distcheck' by leaving VERSION_FILE as an immediate (:=) variable
          and instead creating a two-level <PACKAGE>_VERSION variable, the
          first of which is set from VERSION_FILE by default at make
          recursion level zero (0).

1.6.1 (2018-09-26)

        * Address an issue with VERSION_FILE on clean source code control
          clones or unarchived distribution in which 'make dist' or
          'make distcheck' fail. VERSION_FILE should be and is
          intentionally a deferred (=) rather than an immediate (:=)
          variable to ensure late evaluation AFTER .local-version MAY
          be created rather than when the makefile containing it is
          parsed.

1.6.0 (2018-09-19)

        * Added support to repos.conf for a 'commit' key such that a
          hash or tag other than HEAD for a given repository and
          branch may be synchronized and checked out.

        * Made a minor change to the 'bootstrap' script such that it emits
          the actual action commands that will be executed when the verbose
          flag is asserted.

1.5.3 (2018-09-14)

        * Address a number of issues with building the prepackaged GNU
          autotools subset included in nlbuild-autotools for Ubuntu
          Bionic.

          - Fixed "Unescaped left brace in regex is deprecated" that
            was formerly a warning in Perl 5.22 and is now a hard error
            in Perl 5.26.

          - Address new glibc glob interface changes by upgrading from
            make-3.82 to make-4.1 and applying relevant Ubuntu Bionic
            patches.

        * Add support to the package 'build' script to find and apply
          patches for the above.

1.5.2 (2018-04-26)

        * Since the '--name-only' option only appears in git-2.6 and later
          and there are production systems using git version as old as
          git-1.9, do not use '--name-only' when processing 'repos.conf'.

1.5.1 (2018-04-20)

        * Addressed a number of typos and grammatical errors in comments
          and help output.

1.5.0 (2018-04-19)

        * Added support for pulling down remote package dependencies
          using git submodule.

        * Addressed an issue in which nl_enable_coverage.m4 did not work
          correctly on some Linux distributions by specifying coverage
          libraries under LIBS rather than LDFLAGS.

1.4.4 (2018-02-06)

        * Addressed an issue where 'mkskeleton' failed while trying to
          generate "third_party/Makefile.am".

1.4.3 (2018-02-01)

        * Addressed an issue with NL_{SAVE,RESTORE}_WERROR in which
          -Werror=<specific> was not handled.

1.4.2 (2017-06-20)

	* Addressed an issue with the 'make coverage' target where certain
	  make versions may have sensitivites to trailing slashes in order-
	  only targets.

1.4.1 (2017-06-19)

	* Refactored m4 and autotools auxilliary files to ensure that 
	  third-party content remains under third_party/....
	* Addressed issues with generating distributions on Mac OS X 
	  where GNU software, including wget, is not available in PATH.
	* Addressed issue with missing files in MANIFEST.

1.4 (2017-06-15)

	* Remove package archives and prebuilt in-package binaries.
	* Ensure that GNU tool build process is completely self-sufficient
	  and has no dependencies on installed host binaries.	
	* Add support for generating versioned core and prebuilt package binary
	  distributions.
	* Ensure that 'bootstrap' can work with either prebuilt in-package
	  binaries or with installed host binaries.
	
1.3.1 (2017-05-10)

	* Specify the correct m4 URL.

1.3 (2016-12-05)

	* Added the support for detection of supported C++ version.

1.2.2 (2016-08-29)

	* Use the arguments passed, as designed and intended, to
	  NL_PROG_LNDIR rather than hard-coded values for the GNU cp
	  fallback.

1.2.1 (2016-07-13)

	* Make the 'pretty' and 'pretty-check' targets dependent on
	  $(PRETTY_FILES) and then iterate on a filtered version of $(^) so
	  that make's VPATH engine can be leveraged to find sources and
	  headers that are not in directly stat-able paths listed in
	  $(PRETTY_FILES).

1.2 (2016-06-01)

	* Added support for coding style formatting and checking targets.

1.1.2 (2016-03-19)

	* Improve the code coverage generation process to cover an entire
	  project's source.

1.1.1 (2015-12-10)

	* Properly handle package optionality when using pkg-config to
	  detect external packages.

1.1 (2015-11-10)

	* Added support for a recursive 'install-headers' target to allow
	  packages that wish to leverage it to install their public headers
	  and only their public headers to DESTDIR on 'make install-headers'
	  without performing any additional build actions.

1.0.1 (2015-10-27)

	* Refactored NL_WITH_PACKAGE into NL_WITH_REQUIRED_EXTERNAL_PACKAGE,
	  NL_WITH_OPTIONAL_EXTERNAL_PACKAGE, NL_WITH_REQUIRED_INTERNAL_PACKAGE,
	  and NL_WITH_OPTIONAL_INTERNAL_PACKAGE.

1.0 (2015-03-19)

        * Initial revision with GNU m4 1.4.17, autoconf 2.68, automake 1.14.1,
          libtool 2.4.2, make 3.82, and coreutils 8.21.