Added presenterShareOnly to views (my and spaces) and a new migration
Gemfile redirected to local bigbluebutton_rails

#refs 1280
Added permission to update presenter_share_only field

#refs 1280
Tests completed and internationalization added.

#refs 1280
Merge branch 'branch-v2-1280-presenterShareOnly' of git://github.com/gmiotto/mconf-web into gmiotto-branch-v2-1280-presenterShareOnly
Update bigbluebutton_rails for #1280

refs #1280
Allow changes to :presenter_share_only in SpacesController

refs #1280