Merge remote-tracking branch 'google/release' into 'master'.

Conflicts:
	gflags-vs2003.sln
	gflags-vs2010.sln
	gflags-vs2012.sln
	vsprojects/gflags_unittest/gflags_unittest-vs2010.vcxproj
	vsprojects/libgflags/libgflags-vs2010.vcxproj