feature request: add Lisp window port

[Feyorsh]

Add the lisp patch from nethack-el.

Pros

• Take on the challenges of the dungeons of doom from the comfort of Emacs
• Users of nethack-el do not have to build EvilHack from source (particularly useful on Windows)
• It's very nethack-like to have such an esoteric window port

Cons

• It makes botting significantly easier (also a pro)
• The Emacs-side of the window port lives in a separate repo
• Some degree of code churn as new features are added (although I expect this to slow down pretty soon)

Current deficiencies

• cmd_index in winlisp.c is somewhat out of date and uses some obsolete defines; I still need to clean this up but probably not a blocker
• Lisp version info needs to be moved from the version string to extended version info; prerequisite to merging
• I've since fixed any memory corruption bugs I (and AI) could find and I did another pass to silence compiler warnings, but this is still legacy C code that might have some code smells
• The lisp patch does not support building for Windows on 3.6.7-based variants—this will probably be a moot point once EH is rebased onto nethack 5.0.0
• nethack-el itself does not currently have builtin variant support. I'm currently working on this but it's a bit of a chicken-and-egg problem