Do not show 'Edit' and 'Close' issues menu to non-collaborators

Refs #413
Non-collaborator restrictions on browsing issues.

Non-collaborators are not allowed to change
assignee/milestones/labels when browsing issues.
Refs #413
Override annotations in onClick()
Non-collaborator restrictions in EditIssueActivity

Made it so that issue administration options only show up
if the user is a collaborator on this repository
Closes #419
Move some methods to keep consistency through the class, clean imports
Use Finder to find views