Certs - bugfix cert_whitelist output

* output after cert_whitelist -a or -d purported to be the whitelist entries
  for the requested course, but in fact were all of the entries in every
  course. This commit fixes that.
Modify jquery.timeago to better support i18n

Use string interpolation instead of concatenation of prefix, content,
and suffix. This is motivated by the fact that Transifex does not accept
empty strings for translation (even when pgettext is used to provide
context).
visual styling changes to components and static pages in order to use updated icon button styling for duplicate and delete actions
adjusted unit_spec.js to reflect new HTML structure, and corrected screenreader label for delete button
updated static pages tests to reflect html element change in component.html
Eliminate unused import and gratuitous prints
Merge pull request #2267 from edx/gprice/timeago-better-i18n

Modify jquery.timeago to better support i18n
fixed typo in comment for assets.scss
Merge pull request #2276 from edx/studio/duplicate/visuals

Updates Studio's visual styling of action buttons on components and static pages
add middleware to be able to expire inactive sessions after N seconds

configure middleware

add test for session inactive timeouts

add Studio inactive session timeout test

change login method used

add create_test_account to test

make sure the expected redirect URL is right

fix indenting problem

fix doc string since we moved from minutes to seconds

use utility methods rather than calling another test to set up and activate an account

clean up code violations

respond to PR feedback

use optional params to make code cleaner

pylint fix on test files
i18n Sequence XModule

LMS-1758
Merge pull request #2278 from edx/cdodge/session-inactivity-timeout

add middleware to be able to expire inactive sessions after N seconds
pep8 cleanup
Merge pull request #2296 from edx/cdodge/pep8-fix

pep8 cleanup
Removed French and Korean locales until we add the translation strings
New Discussion forum documentation
Merge pull request #2297 from edx/ahodges-documentation-discussions

Ahodges documentation discussions
Merge pull request #2298 from edx/will/remove-other-locales

Removed French and Korean locales until we add the translation strings
Collect coverage for bok-choy tests
Merge pull request #2290 from edx/jrbl/mdx_stop_printing

Eliminate unused import and gratuitous prints