Add logging to save item
Update `requests` library to 1.2.3
Use oauthlib directly for LTI module
Improve accessibility of forums navigation elements

The home icon and discussion topic drop-down icon now have text that is
visible only to screen readers. The visual change between the icon and the
topic name with down-arrow is now achieved with the CSS visible property
instead of the opacity property, so only one at a time will be visible to
screen readers as well as visually.
Pass hostname to LTI XModule

Necessary for RFC compliance with oauthlib
Remove some cruft from forums SASS
Adding styles to fix issue BLD-221.

If you make the window smaller, and keep reducing it's size, at some
point the controls will not fit, and some will be bumped to the next row.
When the widnow is resized below the width 1024, extra styling rules
will kick in to fix this issue. The word "Speed" from the speeds control
will be temporarirly hidden.
Merge pull request #822 from edx/valera/fix_controls_stack_2_rows

Adding styles to fix issue BLD-221.
Add event tracking with configurable backends
Monitor event tracking time by backend using statsd
Use datetime objects in time field in event tracking
Merge pull request #797 from rocha/track-backend-configuration

Add event tracking with configurable backends
Response.json is now a callable
Add default launch url for lti.
Merge branch 'db/update-requests-lib' of github.com:edx/edx-platform into db/update-requests-lib
Stub headers if scheme not provided.
Merge pull request #931 from edx/jkarni/fix/itemsavelogging

Add logging to save item
reformat for readability
Merge pull request #921 from edx/gprice/forum-nav-accessibility

Improve forums nav accessibility
Merge pull request #880 from edx/db/update-requests-lib

Update `requests` library to 1.2.3