Issue 851 seems to have been resolved and issue 8.5.2 while still open is
not occuring with the latest version of pip-tools.

Update edx-platform dependencies.

BOM-448

BOM-474

BOM-481

BOM-480

BOM-473

BOM-476

BOM-450

Added management command to populate initial history.

Feanil/more bokchoy fixes

made changes as requested

minor fixes

quality fixes

The underlying data is put into json documents that expect unicode
strings not byte strings.  In python2 lxml provided strings that were
auto coerced but in python3 it provides byte strings.

In python2 there would be some auto coercion done so that the orginal
code here works but that's not the case in python 3.

test fixes

python3 compatibility

Remove extraneous pipes

BOM-366

changes made as suggested

minor change

changes made as suggested

test fixes for python 2

removed debug statement

quality fixes

quality fix

quality fix

BOM-475

BOM-420

python3 compatibility, tests fixes

BOM-479

BOM-435

Fixing python3

Blockstore opaque keys moved to external repo

BOM-478

BOM-477