unique index on user course id and achievement id
put award achievement to delayed job
better achievement page
redirect to update grade page for staff accessing submission
Merge branch 'development' of github.com:Coursemology/coursemology.org into dev/achievement_remove

Conflicts:
	db/schema.rb
Merge branch 'development' of github.com:Coursemology/coursemology.org into dev/raymoond_dev
tmp fix for is_creator error
Merge branch 'development' of github.com:Coursemology/coursemology.org into dev/raymoond_deploy