Add admin.py for instructor_task.

This is primarily so that we can manually fail zombie instructor
tasks that are clogging up the queue for a course.
Merge pull request #3554 from itsbenweeks/itsbenweeks/checkbox_doc_example_update

Modifying the checkbox examples syntax so that it works in studio.edge now.
Integrate event-tracking in to the LMS

Support incremental conversion of events from the old API to the new, in order to ensure the new system is working, enrollment events have been modified to make use of the new API.
Create a skeleton of event-tracking developer docs

A first pass at providing details about how to emit events, what to emit etc.
fixes firefox image hidden overflow bug.
puts GA id in quotes
Merge pull request #3523 from mulby/gabe/tracking-shim

Integrate event-tracking in to the LMS
Merge pull request #3558 from mulby/gabe/event-tracking-doc

Create a skeleton of event-tracking developer docs
Bump django 1.4 minor version to 1.4.12 to pick up patches
Merge pull request #3532 from edx/jrbl/certs_pass_course_name_in_dict

Certs: pass course name on queue
Disable draft and edit links during ajax calls
STUD-1485
STUD-1499
Merge pull request #3274 from edx/ormsbee/instructor_task_admin_for_daves_vacation_enjoyment

Add admin.py for instructor_task.
Merge pull request #3560 from edx/adam/disable-links-ajax-2

Disable draft and edit links during ajax calls
Merge pull request #3564 from edx/adam-fix-GA-quotes

puts GA id in quotes
Make release table by PR, instead of by commit
Merge pull request #3551 from edx/victor/remove-iframe-ga

Remove google analytics tracking from iframes used in Drupal course abou...
When sending bulk email check if course is authorized.
Also the idash_mode property is stored seperately for each course.

LMS-2565
Update IFrame documentation
Merge pull request #3527 from edx/sylvia/docs/DOC-295

Add IFrame template documentation
Parameter from_email to send_mail() should be string and not string in list.

LMS-2518