Test related changes and fixes

- Updates json, csv, and xml parsers to pass tests.
- new base class for all tests to extend
- Ads 'runalltests.py' to run the entire test suite
Change Text() object to required named arguments
Fix google voice incoming/outgoing switch bug
Major fixes to iOS 6 parsing and writing

- Shouldn't fail on empty required fields, just warn
- makes a members field on each text for group texts
- adds more robust regression test for testing real files