Merge pull request #1614 from Stanford-Online/wescott-master-exercise-work

Fix for #1613
against #1545 redirects according to codebase.  Also see lots of tests

2 cases:

1. if we get no convenience domain name, i.e. class.stanford.edu/db/Winter2012
* checks if prefix--suffix is a valid class handle in the db
   * if not, do not redirect
   * if so, redirect if we have the wrong codebase (checking suffix=="fall2012"
     to determine whether it should be old or new codebase)

2. if we do get a convenience domain name,
* use CurTermMap to find suffix assoc. with convenience domain name
* redirect if we have wrong codebase (checking suffix=="fall2012"
     to determine whether it should be old or new codebase)
against #1545 redirects according to codebase.  Also see lots of tests

2 cases:

1. if we get no convenience domain name, i.e. class.stanford.edu/db/Winter2012
* checks if prefix--suffix is a valid class handle in the db
   * if not, do not redirect
   * if so, redirect if we have the wrong codebase (checking suffix=="fall2012"
     to determine whether it should be old or new codebase)

2. if we do get a convenience domain name,
* use CurTermMap to find suffix assoc. with convenience domain name
* redirect if we have wrong codebase (checking suffix=="fall2012"
     to determine whether it should be old or new codebase)
#1626 make email lists read-only in admin view
#1619 all email links class->class2go
Merge pull request #1627 from Stanford-Online/jbau-fix-email-list

#1626 make email lists read-only in admin view
Merge pull request #1621 from Stanford-Online/jbau-codebase-redirect

against #1545 redirects according to codebase.  Also see lots of tests
Merge pull request #1623 from Stanford-Online/jbau-codebase-redir-prod

against #1545 redirects according to codebase.  Also see lots of tests
#1641 get report tag from <tr> for table formatted q's
#1571 gets rid of u'' prefix in c2g_examrecordscorefield.value
Fix a few typos and remove unnecessary trailing whitespace in README_SETUP.md
Merge pull request #1645 from hnarayanan/master

Typo and cosmetic fixes to README_SETUP.md
Merge pull request #1629 from Stanford-Online/jbau-email-footer-class2go

#1619 all email links class->class2go
Fixes #1650

Uses the correct exam.image relationships in Video model commit() revert() is_synched()
Changes Video edit action to properly handle exams (using exam and not exam_id in a few places)
Merge pull request #1642 from Stanford-Online/jbau-tr-question-report

#1641 get report tag from <tr> for table formatted q's
Code that fixes #1644

All of the following changes eliminate the javascript console errors
* Re-enables the "video question" thumbnails
* Kelvinator highlighting transitions are now cued by the manifest time,
  instead of polling
* Made the cueing a separate function called in the deferred chain.
Unstyle list of exams in child material listings

* Unstyle child exam list in the course materials items display
  (fixes #1651)
#1635 in-video exams/surveys just resume video
get_live_datetime handles missing ready mode item

* When course_materials.get_live_datetime gets a thing that has no ready
  mode, it helpfully returns a bit of HTML that can be used to tell the
  user this.
  (closes #1600)
trying seeked event instead of seeking in video player