Provide builds or install docs

[s-ol]

Not quite sure how to use this, but it sounds useful :)

I tried loading it via 'Load unpacked extensions' in chromium but get this error:

Error loading Extension

Failed to load extension from: ~/web.lua/fengari-devtools
Could not load javascript 'content-end.js' for content script.

Other extensions that failed to load:

• ~/web.lua

[giann]

This is very much an unfinished experiment. Not really usable right now.