Skip lengthy introduction

Use this URL http://youtu.be/d0uKY2kLKmk?t=6m8s to link to the to the "May 2013 Engineering Software as a Service" - video.
Merge pull request #25 from MaxSchumacher/patch-1

Skip lengthy introduction
Merge pull request #27 from afshinator/dev

Dev
Merge branch 'master' into dev
update hangout link
reduce image sizes
redirect scheduler to courses page
remove scheduler view and static page route
make and run drop cal_events table migration
remove cal event model
remove reference to catching referral codes
remove all scheduler-related specs
hide preferences page since no longer needed by the scheduler
remove before filter authenticating users for scheduler action
remove scheduler styles
remove refs to preferences
revamp users page and make navbar point to study group instead of prefs
pluralize study groups in footer
fix profile page to show completed lessons instead of current projects
remove outdated specs for users index page