Certificates: Add regeneration command

* Adds regenerate_user command, which lets you run certificates for one
  particular user in one particular class, regardless of whether they
  have a pre-existing certificate.
password reset pages use Django templates, not Mako
Release email script: use --no-pager
Add neglected entries
Use known translation if exists to get groupname
Merge pull request #1435 from edx/rc/2013-10-23-fixes

release candidate improvements
Fixed a bug where legacy instructor dash's email editor failed to load
Fixed indentation
LMS: adds correct css/style assets back to password reset and confirm views
Test that instructors can access courses
Remove as_old_location methods
They were incorrect if there were periods in the org or name.
Add cache-based locking to subtasks to ensure that the same task is not running in two workers at the same time.
Merge pull request #1453 from edx/brian/rc-lock-email-task

Add cache-based locking to subtasks to ensure that the same task is not ...
Merge pull request #1452 from edx/rc/2013-10-23-fixes

release candidate improvements v2
Remove unnecessary login_required decorator
Add newrelic instrumentation to forum views
Check for requeued subtasks when in RETRY state.
Merge pull request #1457 from edx/gprice/add-newrelic-instrumentation

Add newrelic instrumentation to forum views
Add isoTime js view.
Video modul changes