This reverts commit 8402be3b.

Ran these suckers through ImageOptim, which crunched 'em down real nice.

 .../js/vendor/ova/images/previous_pressed.png      | Bin 755 -> 665 bytes
 .../static/js/vendor/ova/images/previous_rest.png  | Bin 661 -> 572 bytes
 .../js/vendor/ova/images/zoomin_grouphover.png     | Bin 612 -> 496 bytes
 .../static/js/vendor/ova/images/zoomin_hover.png   | Bin 608 -> 506 bytes
 .../static/js/vendor/ova/images/zoomin_pressed.png | Bin 615 -> 515 bytes
 common/static/js/vendor/ova/images/zoomin_rest.png | Bin 612 -> 496 bytes
 .../js/vendor/ova/images/zoomout_grouphover.png    | Bin 504 -> 397 bytes
 .../static/js/vendor/ova/images/zoomout_hover.png  | Bin 559 -> 461 bytes
 .../js/vendor/ova/images/zoomout_pressed.png       | Bin 561 -> 458 bytes
 .../static/js/vendor/ova/images/zoomout_rest.png   | Bin 504 -> 397 bytes
 common/test/data/aside/static/just_a_test.jpg      | Bin 547 -> 517 bytes
 common/test/data/badges/good.png                   | Bin 298 -> 91 bytes
 common/test/data/badges/large.png                  | Bin 431556 -> 429842 bytes
 common/test/data/badges/unbalanced.png             | Bin 232 -> 86 bytes
 .../static/images/course_image.jpg                 | Bin 12626 -> 12617 bytes
 .../static/images/professor-sandel.jpg             | Bin 453715 -> 447109 bytes
 .../Screen Shot 2013-04-16 at 1.43.36 PM.png       | Bin 8733 -> 1525 bytes
 .../data/simple/static/images_course_image.jpg     | Bin 547 -> 517 bytes
 common/test/data/static/picture1.jpg               | Bin 10905 -> 6857 bytes
 common/test/data/static/picture2.jpg               | Bin 13598 -> 9739 bytes
 common/test/data/static/picture3.jpg               | Bin 14977 -> 9946 bytes
 common/test/data/toy/static/just_a_test.jpg        | Bin 547 -> 517 bytes
 common/test/data/uploads/Signature-0.png           | Bin 31182 -> 14473 bytes
 common/test/data/uploads/Signature-1.png           | Bin 31182 -> 14473 bytes
 common/test/data/uploads/larger_image.jpg          | Bin 1070335 -> 1053927 bytes
 25 files changed, 0 insertions(+), 0 deletions(-)

This was originally contributed upstream by Stanford, circa 2013.

We neither use nor support this feature in its current implementation,
and in fact, we may never have used this production. Until recently, we
had additional chat/Jabber code [1] (in the form of a Jabber djangoapp in
LMS); context there suggests this feature may have never been more than
a prototype. The original author is no longer on the team, so I can't directly
confirm this on our end.

Do you use this feature?

Stanford had already abandoned this Jabber-backed chat implementation,
in favor of an IRC backend, by the time I joined the team in early 2014.

[1] https://github.com/Stanford-Online/edx-platform/commit/dbe52a6b133ab6ff637dea5324f7322da2909070

It was never implemented.
TNL-231

Import asset metadata XML into modulestore.
Optimize importing many items of asset metadata by avoiding multiple
round-trips to MongoDB.

OPEN-328

Make split_mongo assert block identity uniqueness only over (block_type, block_id) tuples [LMS-11364]