Update to 0.7.0.1

changes:
 - Relax dependency on attoparsec
Update to 0.6.0.1

ChangeLog:
Version 0.6.0.1 (2013-12-01) *World AIDS Day*
#### Package changes
* Change QuickCheck lower bound from 2.6 to 2.5

#### Contributors
* [Michael Snoyman](https://github.com/snoyberg)