Adds val trancripts in outcome of get_transcripts_info and rest of flow remains the same and also add fallback  to edx-val rtanscripts for mobile accessible video endpoints.

Purpose of this, is to serve transcripts from edx-val if the requested transcripts are not found in the contentstore i.e. that's where all the transcripts are living to date.

EDUCATOR-1216

Tooltip text under lms->courseview->progress tab->chart
was not under any translation, causing it to appear untranslated for
learners. This would enable its translation to any language.

LEARNER-2607

Mock out the static_replace modules in the proper location.

EDUCATOR-558

LEARNER-2468

remove try/catch block and associated test for EDUCATOR-1134 following verification that no stage or production courses have issues related to dates

date has passed

EDUCATOR-1134

EDUCATOR-1136

Attributes come in as a list of dicts with strings as keys and values.
Implicitly casting each result as a tuple causes the code to split the key string into it's characters.
This yields a list of characters, the first two of which are placed into the variables "attr_name" and "attr_value".
This is not only wrong, but because keys tend to be more than 2 characters, the net result is:

"ValueError: too many values to unpack"

Separates archived courses into a different tab on the Studio index page.

Data is rendered synchronously, but tests are added to ensure that no new sql
or mongo queries were required.

This has been causing a huge memory leak, wrapping the call in this
context manager properly cleans up the 'records' entries.

EDUCATOR-274

This reverts commit 2d6b477e, reversing
changes made to 7799c4ad.