Enhancements to mkfiles.pl and Recipe to arrange for the auxiliary

Enhancements to mkfiles.pl and Recipe to arrange for the auxiliary
command-line programs (solosolver, patternsolver, mineobfusc) to be
built as part of the normal Makefiles. This means mkfiles.pl now has
the capability to compile a source file more than once with
different #defines. Also, fixes for those auxiliary programs and one
fix in midend.c which the Borland compiler objected to while I was
testing its makefile generation.

git-svn-id: svn://svn.tartarus.org/sgt/puzzles@6066 cda61777-01e9-0310-a592-d414129be87e