Phasor kinda working + some utilities for testing / debugging + cleaned a bit the build

Sorry for this quite messy pull request. My commits are quite messy, and everything is kind broken :)
Yeepeee!!!

I removed karma, I added dsp-test-files as a sumodule, and created a few helpers to help testing against reference files. If a test fails, an html page is generated to compare the expected result with the actual result visually. The report could be improved to be more useful, but I think already this is very helpful.

For doing the testing without karma, I messed around, adding things like `if (typeof require !== 'undefined') var _ = require('underscore')` and also `ArrayMath = require('../dist/webarraymath')`. This is super messy, but I just wanted to be able to work somehow, and nothing that can't be cleaned ...

phasor kind of works, but it fails against the test file. Problem is probably something with modulo. Cause it seems that when the reference phasor hits 32767, our phasor hits 0, and after that, the numbers are the same again.