[TIMOB-14586] Support textStyles introduced in iOS7

Fixes 
[TIMOB-14586](https://jira.appcelerator.org/browse/TIMOB-14586)
Also fixes some of our fallback code. 
[TIMOB-14796](https://jira.appcelerator.org/browse/TIMOB-14796)

Regression - KS->Custom Fonts