Merge branch 'staging'
Update to rails 3.2.11
Merge branch 'staging'
Add concurrency options for other queues.

Because we're overriding the concurrency for the outbound mail queue,
the default behaviour of having concurreny=1 for each task is lost,
and instead Procfile tasks that aren't listed here get concurrency=0. Gah!
Experimentally rename threads to discussion threads in menu
Tooltips for menu items (experimental)
Self-document users page
Table styling
Set table style site-wide
Improve link style and make inline links clearer
Improved bullet and inline link style handling
Improve /groups/id-moniker/members page
Show people in alphabetical order, favouring display name over full name
Tidy up group page right-hand side
Add image to group membership page and tidy table layout
/user/locations/new layout/usability improvements
Show number of membership requests on group front page panel
Add labelling to explain dashboard tab items
Add labelling to issues page
Text on issue page, with link through to administrative threads area