Helper method to check if an user is an admin
Sudo make me a sandwich

Create sudo ability for admins to sudo into anybody to test stuff up!
But available only in development.
Add some sample members as seed data for users
Clean up Sudo routes and controller
Rename Sudo to Su
Merge pull request #1 from hackerschool/su

Style cleanup for Su
Fixing code review suggestions
Show a list of users to select when trying to su
Show names instead of emails in su index; get rid of helper
Merge branch 'su'

Conflicts:
	app/models/user.rb
Minor notifications dropdown css fixes
Merge branch 'master' into pinned-threads
Use is_admin? instead of satisfies_roles?