Create a ProjectUser table allowing to specify multiple admin to a project/fork
Add a generic method to check if the user logged in is an admin of a specified repo
Ensure that only admin repo may edit a ticket
Make sure only admin repo can create pull-request for this repo
Include in all templates the `authenticated` variable informing if the viewer is authenticated
Everyone cam view issues, but only the authenticated repo admins may edit its status
Only show the forms is the user is authenticated
Only authenticated user can see the 'Pull-request' link on the log view
Rename `content` into `issue_content` in the IssueForm
Adjust the issue_content css to make the textarea looking a little better