consider defining a custom lua editor mode

[pq]

defining our own editor mode would un-gate a few things:

• updating syntax (update ace syntax to fix lua 5.3 bitwise op parse errors  #9)
• clickable links (feature: clickable links in lua content editor #77)

in the long run, it could further help w/

• customized code completion
• improved doc integration

[pq]

quick update: i've done some digging, specifically targeted at updating syntax (#9). the rub there is that we need to update the parser which does syntax validation in a web worker. the parser fix looks easy however i've not been able to get the worker bit sorted out.

tagging this as "help wanted" in case more web-savvy folks would be up for lending a hand.

/cc @anthonybarsotti @jlmitch5

[pq]

for context, here's a branch that gets us to where we'd like to wire-up the worker: pq@02aa78a (createWorker contrib is commented out in lua.js).