fixed toggle text - add responsive behavior

Hi I been done some minor changes in the code. As you said I can't share my changes with the original author, so I share my changes with you (and the others github users).

Changes:
- fixed toggle text (Source / wysiwyg button text). It was impossible to localize this texts.
- add responsive behavior. Now when width is defined it add a "max-width" style instead a "width". I've also change the background headers and added minor changes to the css to allow multiples rows in the same header.
- uglify.js comppression for packed version

Un saludo!