Fix userbadge assignment within overlay
remove unneeded import
Also require page.edit_head for container page edit
Proper permission check for container page edit in template

This is now consistent with the permission checks on the actual edit
controller and with show_sectionpage.
Optionally require user to check terms on register
Merge pull request #900 from nidico/feature-fix-userbadge-assignment

Fix userbadge assignment within overlay
accept_terms: improved error message
allow to link to inline rows

the link is available from the expand button
fix page.edit_head error msg
Merge pull request #901 from nidico/feature-fix-container-page-edit

Fix containerpage edit permissions
fix agree terms wording
fix guard state

the guard decorator was not thread-safe. This allowed perpetrators to
let other users execute controller functions with manipulated
parameters. However, I could not find any critical exploits based on
this bug.
Merge pull request #903 from nidico/feature-check-terms-on-register

Optionally require user to check terms on register
Merge pull request #905 from xi/feature-fix-guard-state

fix guard state
Merge pull request #904 from xi/feature-link-to-inline-row

allow to link to inline rows
Add hack which redirects fairnopoly activation links to its instance

nidi forgot to set the instance in the invite script. Therefore the need
of this ugly hack.