Cleaning up js lint errors.

I've removed unnecessary semicolons. Added necessary semicolons. Pulled function creation out of loops. I've updated the jshint ignore file to properly scan mitro for javascript files. Removed the temporary suppression of some lint warnings in the jshint file after fixing the errors corresponding to those rules.
I think the change to `===` breaks the intent of the original function, and this is a time where jshint's [`eqnull`](http://jshint.com/docs/options/#eqnull) may come in handy.