Force libstdc++ for upgrade/legacy compatibility.

From J. Howarth
Fix bootstrap issue.

From J. Howarth.  I'm not sure what the ramifications of disabling NLS ultimately are.
For MakeMaker-based packages, extend past practices.
Fall back to Fink's cvs if /usr/bin/cvs is missing.
Check that the vcs executable is a file and then check that it's executable, to avoid pathologies like a "cvs" directory.
Hey, let's actually have this work.