make openendedchild and open_ended_module_v1 act enough like xblocks to get xblock 18n

Some messages generated by the comments service are not readily
translated because they come from third-party libraries. Thus, we plan
to try to avoid showing any comments service generated message to the
user. This check preempts the only end-user-visible CS-generated error
message that we are presently aware of.

Added feature setting 'DISPLAY_HISTOGRAMS_TO_STAFF' to configure display of histograms in Staff Debug Info panel.

Generating histograms requires scanning the courseware_studentmodule table on
each view. This can make staff access to courseware very slow on large courses.

Default is False.

LMS-1199

Renamed feature setting 'DISPLAY_HISTOGRAMS_TO_STAFF' to 'DISPLAY_DEBUG_INFO_TO_STAFF' to better communicate its purpose.

Default is True.

LMS-1199

STUD-1151

Student logins to edx, plays video, selects position, closes
browser, opens video, position is restored.

BLD-385

screen readers. Also, the mathjax message should be wrapped to prevent
non-IE browsers from complaining about a feature that is IE-only.

The front-end code for rendering a thread always makes an AJAX request
for the resopnses, regardless of how the thread was accessed (directly
by URL or by selecting it from the thread list). Previously, when
a user accessed a thread directly by URL, the LMS would initially
request the thread from the comments service with responses, but that
response data was never actually used. Now, the responses are not
fetched with that initial query.

LMS-2192

[LMS-179]
[LMS-209]
[LMS-1345]

Removed inappropriate section tags. Because screen readers announce each section, they should not be used unless they are actually defining meaningful sections.

with code to translate between addressing schemes based on app
and persistence layer addressing scheme specification.

STUD-1206

add a test case for enrollment caps

pep8 fix

When creating an instructor task total_num_items may change between the
time it and the number of subtasks is calculated and the time the
subtasks are actually queued (all of this cannot happen in one transaction).
In such a case the extra items are distributed among the subtasks of the
last query.

LMS-2090

Caution! This is backwards incompatible

Make XBlock client-side runtimes proper classes, so that handlerUrl can
be defined in a per-runtime way, and we can have multiple runtimes on a
single page.

[LMS-1630][LMS-1421][LMS-1517]

Fixed i18n in templates

Added a banner that students can use to dismiss the "you have failed reverification" message.  Also, removed unused code, wired up the sidebar for design

Also, refactored code representing ReverifyInfo

Also, removed an unused template