Set empty aws credentials to None.
sending template pdf with certificate request
fixing some typos
Fixed password reset message

LMS-1507
CSV Reporting of Shopping Cart Purchases, with tests

squashing to one commit to make cherry-picking by feature possible
Basic test fix
Recover from error loading forum thread list

When a user attempts to load more threads in the forum navigation
sidebar, reset the state of the world so the user can retry, and alert
the user appropriately.
Add focus trap on forum navigation thread loading

For accessibility purposes, it is bad to allow a user to initiate
loading of additional threads in the navigation sidebar and then shift
focus away from the sidebar, only to have focus snap back when the
additional threads are loaded. Now, we trap focus on the loading element
as recommended by our accessibility consultant.

JIRA: FOR-238
changes to allow multiple choicetextresponses in one problem
Fix bug in grabbing course enrollments.

LMS-1475
Update AUTHORS
Removed null bits
Merge pull request #1693 from edx/flowerhack/fix/password-reset-messages

Fixed password reset message
Increased timeout for element count in HTML test
revises .gitignore file to include static css directories and remnants of devstack setup
Change preview view method to use RESTful URL.

STUD-848
If student has not passed verification, issue an honor code cert.

Also, display a message on their dashboard.
Use class methods to find the enrollment mode.
Separate all db ops from modulestore ops
Show error on invalid html in course handout edit + Added tests
STUD-293