Add Button widget and stubs for Toggle and button groups
Merge remote-tracking branch 'origin/master' into mattpap/buttons
Restructure buttons, groups and button groups
Add support for font-awesome 4.2.0 (using bk-fa- prefix)
Add support for Icon widget
Add convenience Session.poll_document() method
Implement checkbox and radio groups
Use bk-bs- prefix in button.coffee
Add bk-bs- infix to data- selectors in bootstrap/less/*.less
Implement checkbox and radio button groups
Implement toggle button
Add spacing between button's icon and text
Make icons work on the server (no static pages yet)
Preliminary implementation of dropdown buttons
Add glyphs/buttons_server example
auto-open examples
Merge pull request #1131 from ContinuumIO/mattpap/buttons

Button widgets