Proper example for bootstrap input groups
Closes #2241
Merge branch '4.0.1-wip' of github.com:FortAwesome/Font-Awesome into 4.0.1-wip

* '4.0.1-wip' of github.com:FortAwesome/Font-Awesome:
  Updated the icon count in the readme
  adding pointer to rtfm for syntax changes
  adding upgrade wiki page to documentation