started loudness
extraction of loudness coefficients
adds spectral flatness extractor
implemented perceptual spread
changed buffersize, changed number of bark bands
major improvements

loudness now outputs band-specific and total
perceptual spread is correct according to GP2004
Merge branch 'perceptual-spread' into loudness

Conflicts:
	main.js
adds zero crossing rate
fixes merge conflicts, adds to the readme
added perceptual sharpness
fixes merge conflict
Merge pull request #40 from hughrawlinson/loudness

Loudness
spectral rolloff
spectral rolloff
fixes merge conflict
Merge pull request #39 from hughrawlinson/zcr

Zcr
fixes merge conflicts
fixes merge conflict
tweaked readme and fixed index conflicts
fixes another merge conflict