Log Message:
Update mathomatic to 11.1b.

Changes since 11.1:
Added Java code generation (usage: "code java").

Added "list export" option, to display equations in exportable format.
They can be cut-and-pasted to another math program with this option.

Added a blank line after every equation listed with the "list" and
"code" commands.  Looks better.

Made "MAX_VAR_LEN" completely flexible (can be set to any value; set \ 
to 80).

Improved factoring of polynomials with repeated factors by trying to
differentiate with respect to every variable.