[#82966592] Clean up figures controllers and policies
loosen the paper policy
[#82966592] remove unneeded policy [ci skip]
upload_attachment -> update_attachment
Merge pull request #630 from Tahi-project/figure-policy

[#82966592] Clean up figures controllers and policies
Relax paper policy
[#82988170] fix specs and some markup
Merge pull request #631 from Tahi-project/bug-fix-adding-task-participant

Loosen the paper policy
Handle 403 gracefully on `papers#manage`

Makes the `manage` route symmetric with other paper routes, which
redirect from the policy.
restore missing file
Merge pull request #632 from Tahi-project/paper-manage-redirect

Handle 403 gracefully on `papers#manage`
Pull from paper.plos_authors and serialize all plos_authors to keep things in sync when positions change
[#83057042][bugfix] Admin should not be able to uncheck a journal role permission without entering edit mode first
Upgrade to Ruby 2.1.5
Merge pull request #635 from Tahi-project/bug-fix-plos-authors-streaming

Keep author creations in sync across browsers
Call ErrorHandler on window
Merge pull request #637 from Tahi-project/fix_error_handling

Call ErrorHandler on window
Allow source to be a changeable computed property
Replace chosen with Select2 on contributors overlay
Throw errors where Bugsnag is not available