Rename rounded-corners -> border-radius
Remove bootstraps border-radius for buttons
Rewrite the button widget

- Fewer available colors (red and white)
- Fewer available sizes (large and medium)
- Different UI controls (single preview button)
Adapt existing button widgets for bootstrap 3
Fix leftover input classes
Fix leftover control-group classes
Fix leftover icons
Fix leftover control_group fields
Use correct class for radio input wrappers
Replace input-button-align with input-groups in admin
Rename hints validator field to help_block
Replace remaining hint blocks with help-block
Add sheet with class wrapper for editing publication
Set img max-width to 100% in publication listing
Add btn-default class where missing
Cleanup remaining bootstrap2 leftovers