Include keysym for XF86AudioMicMute.

* keysyms.lisp: XF86AudioMicMute is #x1008FFB2
Remove clx-truetype from user's dependency documentation.
Merge pull request #90 from tmurph/FIX-xf86audiomic-keysym

Include keysym for XF86AudioMicMute.
Merge pull request #91 from KeiferMiller/master

Remove clx-truetype from user's dependency documentation.
Fixing CLISP dependency