Fix deprecated skylark (#1542)

Fix Skylark deprecation warnings

Fixed several instances of deprecated Skylark behavior

* Used depset.to_list() when iterating
* Avoid depset + operator
* Remove instances of FileType
* Use native.repository_name() and package_name instead of
  REPOSITORY_NAME and PACKAGE_NAME.

Also, upgraded vendored Skylib to 0.4.0, since it had some deprecated
stuff.

This change does not fix deprecated uses of args.add. That will
require more work.

Fixes #1534
Fixes #1535
17 files changed