Upgrade `requests` module to 2.3.0
Upgrade `requests-oauthlib` to 0.4.1
Upgrade `oauthlib` to 0.6.3
Add argument.
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
log stop_video event
The LMS should serve favicon.ico also when a theme is enabled.
Added mising tinymce.js to static_htmlbook.html.

LMS-2848
Pass storage_url and token values as parameters to StudentNotes init.

LMS-2848
Add possibility to run bok_choy tests in local env.
Merge pull request #4190 from edx/usman/lms2848-htmlbooks-fix

Fix for htmlbooks
Lower logging level in grading condition from exception to info

addresses part of LMS-2907
Merge pull request #4181 from edx/alex/allow_bok_choy_in_dev_env

Add possibility to run bok_choy tests in local env.
Merge pull request #4192 from edx/adam/change-logging-level-gradding

Lower logging level in grading condition from exception to info
Redirect Chinese students to a Chinese CDN for video.
Remove pirate and lolcat translation files to prevent accidental display
Merge pull request #4197 from edx/sarina/remove-en@-translations

Remove pirate and lolcat translation files to prevent accidental display
Merge pull request #4196 from edx/oleg/video-caching

Redirect Chinese students to a Chinese CDN for video.
Merge pull request #3769 from shindere/favicon-fixup

Improves the way LMS serves /favicon.ico
Move video descriptor instantiation in tests to single place.