Upgrade `requests` module to 2.3.0
Upgrade `requests-oauthlib` to 0.4.1
Upgrade `oauthlib` to 0.6.3
forums: fix assign_default_role to use the correct constant.
Add argument.
Fix the CoursePagesTest
update opaque keys dependency to fix install
Bump opaque_key dependency to 0.1.1
Allow xblocks to be added as advanced problem types
shim to update ruby/node, not python reqs
missed commit
Add scope/field selector settings for LinkedIn provider.

This change adds three new configuration variables to third_party_auth's LinkedIn provider:

* SOCIAL_AUTH_LINKEDIN_OAUTH2_SCOPE,
* SOCIAL_AUTH_LINKEDIN_OAUTH2_FIELD_SELECTORS,
* SOCIAL_AUTH_LINKEDIN_OAUTH2_EXTRA_DATA

Being able to configure these additional settings is useful if you want
the LinkedIn provider to pre-populate the email field when a new user
registers via the linkedin provider.

The Google provider prepoulates the email field by default, but if you
want LinkedIn to do the same, these two settings should be set to:

SOCIAL_AUTH_LINKEDIN_OAUTH2_SCOPE = ['r_basicprofile', 'r_emailaddress']
SOCIAL_AUTH_LINKEDIN_OAUTH2_FIELD_SELECTORS = ['email-address']

For more info see:
http://psa.matiasaguirre.net/docs/backends/linkedin.html
trigger change event for file field while uploading pdf
STUD-1775
Add examples of html5 videos to docstrings.
Merge pull request #4104 from edx/alex/return_html5_video_sources_in_docstring_for_easy_testing

Add examples of html5 videos to docstrings.
implement forums endpoint for searching users
Merge pull request #4041 from edx/jsa/forums-search-users

implement forums endpoint for searching users.
Merge pull request #4089 from edx/zoldak/courses-test

Fix the CoursePagesTest
Merge pull request #4054 from edx/zub/bugfix/std1775-uploadpdfbutton

trigger change event for file field while uploading pdf
Fixed MATLAB Run Code bug with answer boxes.
LMS-2807