Update README.md to include options documentation.
Add padding so legend and icon don't overlap.
Cleanup and fix for initial state race condition

- Changed detection of initial state of fieldset to use hasClass instead of more expensive attr & search. 
- Changed class toggle to chained remove/add class so that correct classes are added to fieldset on load.
Merge pull request #1 from radioactiv/master

Documentation cleanup, style fix, and better state on init.