Make methods instance methods
Clean up HTML
Standardize the comment language
Reference all methods as instances
Add methods:

- email()
- tel()
Add textarea() method
A few changes:

- Removed indent() (sorry @CraigChilds94 :()
- Cleaned up use of quotes
Revert to string interpolation for buildAttributeList()
Clean-up post-type registration
Merge branch 'entry-post-type' of https://github.com/tannwestlake/formulate into entry-post-type