Created seed file

Included database_cleaner and made factories create random data using Faker
Filled seeds.rb file (usage rake db:seed)
Basic functionality of /classroom for teacher and student

Also updated classroom controller to send user assignments sorted by due date
Merge pull request #16 from whoisglover/classroom_index

Classroom index
created submissions create route and route test
Merged created submissions route and test with master.
Merge branch 'master' into user_routes
Merge pull request #17 from whoisglover/user_routes

Submission route create and test
Merging new classroom views with master

Merge branch 'master' of https://github.com/whoisglover/FrogPress into new_classroom_views