Changes since 12.7.2:
Improved documentation.
Added display of maximum memory usage to version command.
Allow read command in the Mathomatic library and fixed memory leak with it.
Added echo command per a user's request.
Improved factoring out constants, to make all coefficients reduced integers by
factoring out their gcd.
Added gcd_verified() function, to weed out false floating point gcds.
Made limit command say whether it is substituting or solving.
Added "mathomatic.desktop" and "mathomatic.png", which are the desktop and
icon files for Linux.
Minor code, documentation, and makefile improvements.
Added "tests/quartic.in" and fixed incomplete simplification in the calculate
command.
Allow upper case when parsing infinity constant name "inf", required by CygWin
version and maybe others.
The makefiles no longer strip the created executables.
Reordered source code so many functions can be defined returning "void" (which
means no return value).
Added "tests/how_limit_works.in" tutorial and restored "doc/notes.html".
Testing change to only one kind of partial unfactoring (partial_flag =
true/false, default true), completely distinct from full unfactoring. Used
throughout, let me know if this breaks anything.
Added "simplify fraction" option, which simplifies like Maxima's ratsimp().