Change font-awesome gem.
Add missing style to button.
Changes for new icon names.
Replace some old font syntax with new helper method.
Replace old string concatinated font syntax with new helper method.
Update font syntax used in icon_link_to helper.
Apply fixed width class to some icons.
Remove icon_link_to helper.
Merge pull request #194 from t-bullock/fix-button-style

Add missing style to button.
Merge pull request #195 from t-bullock/font-awesome-4

Font Awesome 4 support