Import bmake-20170711
Several misc cleanups, refactor main() to reduce size.
Adds -v option to always fully expand variables (only interesting to NetBSD)
And in particular (from ChangeLog):
o meta.c: ensure command output in meta file has ending newline
even when filemon not being used.
When matching ${.MAKE.META.IGNORE_PATTERNS} do not use
pathname via ':L' since any ':' in pathname breaks that.
Instead set a '${.p.}' to pathname in the target context and
use that.