Started refactoring into actions
Rethinking actions a lot
Finishing work on actions; it is now sealed and independent of the gui
Added two more ui-actions (quit, save)
Consolidating GUI stuff into new gui module
A new ocamlllex/menhir lexer and parser
Better generation and cleanup of version.ml
Changed the old parser to use Result.t in preparation of move to Menhir
Finishing the transition to the Menhir-based parser
Slight refactoring of the treatment of quantifiers
Renamed form_ things to syntax_ things, and syntax_prs to syntax_io
Finished plumbing the new GUI.

Need to change the treatment of variable renaming
Lots of bugfixes to all aspects of the new gui
Minor update to the documentation
Add '+' and '-' to increase and decrease the number of history lines.

Also a new command line flag -hist-lines with clamping to (0..20)