Upgrade factory_girl_rails to 4.5.0
Update Gemfile
Upgrade to new FactoryGirl syntax

Conflicts:

	spec/controllers/courses_controller_spec.rb
Merge branch 'rspec-3' into factory-girl-4
Update Changelog.md
Merge branch 'rspec-3' into factory-girl-4
Merge pull request #214 from rage/factory-girl-4

Upgrade to FactoryGirl 4