Form and db fix
Revert "Form and db fix"

This reverts commit 039799091b9fa7df0552ebe7f48a474cf09707d7.
Course tabs added.
Removed migrations
Course creation modal added. No course code yet.
Use teacher.full_name instead of using first_name and last_name separately.
Inform teacher when no courses are created.
Fix typo in no_courses partial
Displays active tab without content. Fixes #39.
Fixed teacher spec
Fixed first tab active by default
Merge branch 'courses' into teacher-profile

Conflicts:
	app/models/course.rb
	app/models/teacher.rb
	app/views/teachers/home.html.erb
	db/schema.rb