Log message:
Set BUILDLINK_ABI_DEPENDS correctly (with +=, not ?=)
It turns out there were a lot of these.

Log message:
Update gnustep-make to 2.4.0. Notable changes include:
   * Parallel building supported using e.g. make -j 2
   * Support source files in subdirectories without using a subproject.
   * Support header files in sub-subdirectories.
   * Batch-compile Java files (much faster).
   * Fixes for building documentation.

Log message:
Installation dirs should not contains PKGREVISION,
so use PKGNAME_NOREV instead of PKGNAME.
XXX: it may be sufficient to use just PKGBASE, but keep as-is.
XXX: and other than libFoundation are not using the subst line,
XXX: so maybe it should be moved to the package Makefile.

Log message:
Redo fix for leaking .buildlink references in a more generic fashion by
using the real path in CPPFLAGS etc. The wrapper framework will translate
those back.

Add some more substitutions for additional directories to help other
packages being destdir safe.

Log message:
Don't use the buildlink fake gnustep directory here as it would leak
the build path into the binary package. Bump revision.

Log message:
Remove @dirrm related logic.

Log message:
Convert @exec/@unexec to @pkgdir or drop it.

Log message:
Remove @dirrm entries from PLISTs

Log message:
Ran pkglint --autofix on the devel/ category. Most of the changes are
simple white-space issues like indentation and trailing spaces. The
others are cross-references for Makefile.common.

Log message:
Use standard location for LICENSE line (in MAINTAINER/HOMEPAGE/COMMENT
block). Uncomment some commented out LICENSE lines while here.