TODO

* Optimise parsing
- store 'a' commands in separate string and add all at once when another command comes; minimises inserts into large string.
- use array instead of string: can use gets to parse more lines, can store meta info from last parse
- calc lineno in emacs from last known lineno if pos is closer than point-min (steal line-number-at-pos code)
- parse minimal subsection: most chars don't alter much except "'%({[` <<END \n
   start parsing from up-sexp and check that end-sexp still of same type otherwise parse to EOF

* Code DRYing
   build face lookup table with ruby and send to emacs


DONE

* :@@abc should be symbol for variable font