Only let users edit their own coop.
See shift info on all coop pages.
Merge pull request #13 from daf-/only-edit-own-coop

Only let users edit their own coop.
Merge branch 'master' of https://github.com/daf-/coop-site into admin-creates-all-shifts

Conflicts:
	app/views/coops/show.html.erb