add/edit tags of navigation, add instructed_terms table with functions implemented, error in event destroy.
disable student to edit their profile (semester, major, availability) after he filled the form.
Fix deleting event bug
Calendar is working
fix bugs, add tooltips, and style refine
Merge commit '116303557ebf5930d32d3647bc9782058bd115cd' into wdn

* commit '116303557ebf5930d32d3647bc9782058bd115cd':
  Calendar is working
  Fix deleting event bug
Remove all controller specs
Disale action on projects for students
Sponsor Preferences
enable students to view projects and preference status
Merge commit 'a5fc9f8813f195a5e85353ef404687f59b907d17' into wdn

* commit 'a5fc9f8813f195a5e85353ef404687f59b907d17':
  Sponsor Preferences
  Disale action on projects for students
  Remove all controller specs
only enabled applied projects can be viewed by students
Add rails12factor
Set ruby version
Add Procfile
Disable pry in production
Pg
And I'm an idiot
Should fix Procfile
fix some bugs, change instructor navigation