Checkpoint
%s/\<m\([A-Z]\)/_\l\1/g  e.g. mFooBah -> _fooBah
Escape handling cleanups.
Protect terminal dispatches. Usage SHELL by default.
Checkpoint - bob is deleting stuff!
Temp checkpoint
Refactoring: {enums,bit_sets}.{h,c}xx
Implemented ModeSet.
Implemented title support.