Remove autoplay for video in course about page

The iframe was generated with autoplay=1, which, sometimes, would cause
the video to play in the background.
missed rst
further explanation on entry_points
add infinity symbol to calc preview
Add info for polls
Fix URLs for static resources
Embargo Middleware feature

Adds configurable middleware in common/djangoapps/embargo that
allows specific courses to comply with US Export regulations by
embargoing students from specific countries, whilst simultaneously
allowing other courses to be freely open to all.
Django-admin for Embargo feature

Allows specification of countries to embargo, what course(s) should
apply embargo restrictions, and whitelist/blacklist capability for
specific individual IP addresses.
Tests for embargo middleware feature
Start documenting Staff Debug Info

STUD-1273
Update schema for bok-choy database

Finalize tests for embargo middleware app
Students not receiving credit for peer assessment.
ORA-330
Display only the first component name in the page (and nav) title.
STUD-1351
Fix youtube captions that disappeared with multi-language caption support

[BLD-889]
Fix case where both old and new transcripts are uploaded, but transcript language isn't one of the new transcripts.
Add error notification for XBlocks in Studio
Further updates to Polls
Merge remote-tracking branch 'origin/release'

Conflicts:
	cms/envs/common.py
	lms/envs/common.py
adding in gray versions of social icons for use in new email template. Using new name to ensure old links and existing emails using older templates still stay active
Merge pull request #2759 from edx/release-and-merge-conflict-resolution

Release and merge conflict resolution