Features of interest:
Allow setting target local variables (similar to gmake)
In META_MODE .MAKE.META.CMP_FILTER can be used for filtering commands
before comparion.
contrib/bmake/mk/cc-wrap.mk is an example of using these
See ChangeLog for the gory details.
o allow env var MAKE_OBJDIR_CHECK_WRITABLE=no to skip writable
checks in InitObjdir. Explicit .OBJDIR target always allows
read-only directory.
o Fix building and unit-tests on non-BSD.
o More code cleanup and refactoring.
o More unit tests
Lots of new unit-tests increase code coverage.
Lots of refactoring, cleanup and simlpification to reduce
code size.
Fixes for Bug 223564 and 245807
Updates to dirdeps.mk and meta2deps.py
