Add staff graded assesments xblock to requirements

(cherry picked from commit 9949c3d490408aba8a61259439412d273c5c2a95)
Fix a bug in Individual Due Date Extensions (IDDE).

The IDDE implementation relied on a StudentModule being created for a
particular block in order to set the extended due date on that block.
Since StudentModules seem to be created on demand whenever data is
written to an attribute with Scope.user_state, it meant that if a
homework problem hadn't yet been touched by a student it was possible
that the due date extension wouldn't take effect for that problem, even
if the due date extension was successfully set for the parent unit.

This patch fixes this problem by creating new StudentModules as
necessary in order to make sure extended due dates propogate properly to
all problems in a unit.

(cherry picked from commit 209c15d1518c7a0df8dd44ff8e0a900cd1c9fdc4)
Add ADDL_INSTALLED_APPS to studio for parity with lms

(cherry picked from commit faefba91826412e51610ce107a10f52ab0b6e2b6)
Adding django default log handlers into logging configuration

(cherry picked from commit cc0832750d6b75cb31d5021eb12e0b244e9d4478)
Added matplotlib and pandas to sandbox requirements
Adding requests so symmath works
moved from post to base

(cherry picked from commit ccb36ba0a8f4a0461413127324dd3a6b226d27ff)
Pinning edx-sga
Changing pin to pre-ok branch