Merge pull request #353 from dessibelle/text_email

Added text_email field, props @dessibelle
Revert type=email style. will use cmb_text_medium class to style
Update readme with props
Clean up code a bit, clean up whitespace, and use cmb_text_medium class on email/url fields
fix whitespace/indentation issues
Remove optional validation. They can use `is_email` filters if needed.
Merge branch 'trunk'