Implements `util.format` and `util.inspect`, formatted `console.log`

Caveats:
- <del>adds some failing tests due to miscellaneous colony runtime issues (issues now cross-referenced, see https://github.com/natevw/tessel-runtime/commit/4608b513edf8f8221c4d40ed42ba1c230e05c9c1)</del>
- <del>`console.log` behavior not yet fixed (i.e. #176)</del>
Ah, shoot, is this the speed regression? Is there any higher-level (caching) require available on the Lua side?