Log Message:
maxima: update to 5.41.0.

Cross-compiling changes and improvements.
Documentation changes and improvements.
Build/installation improvements.
Updates to examples.
Changes and improvements to test system.
Changes and updates to nightly builds and tests.
Added the rules to build a snappy package.
Windows installer improvements and fixes.
Improvements to Windows maxima.bat.
Debian build improvements.
Compatibility improvements with diverse LISP compilers.
Plotting improvements; improved GNUPLOT error handling.
Code optimizations.
Removed some old/unused code; cosmetic changes.
New test cases.