Update README
Some refactoring and more constant formatting.

Add jshintrc file. Clean up transition method to get ready for #21.
Fix bootstrap 3 grid demo at mobile issue.
Add `visibility: hidden` to concealed items so that overlapping hidden items cannot be clicked. Closes #21.

Other assorted improvements to event handling. Broke up `_transition` into smaller methods.
Docs update/fixes
v2.1.1 for #21