switch dependency from Parsec to Attoparsec

- remove dependency on Ranges
- change behaviour to strip commands and whitespace
add 'canonicalizeEmail' utility method
actually export the canonicalizeEmail function
add test suite, move parser into its own file
use takeWhile1 in a few places to take advantage of attoparsec
Merge pull request #4 from Porges/attoparsec

Attoparsec