Allow course staff to submit raw score to remote gradebook

[pwilkins]

Allow course staff to send edX raw score to remote gradebook.

Justification: Currently edX's remote gradebook feature sends a calculated grade that is between 0 and 1 inclusive. The remote gradebook expects a raw score because it performs the calculation itself. Currently, the course staff has to manually convert edX's calculated grade back to a value that the remote gradebook can use.

The fundamental work has already been merged into edX with PR#10395 (https://github.com/edx/edx-platform/pull/10395). Left to do is changing the CSV file that is used to send grades to the remote gradebook.

@pdpinch

[pwilkins]

Changes to edX will create a CSV file in this format for export:

External email	Multiple Choice Questions	max_pts
[email protected]	2.0	3.0

[pdpinch]

We've gotten some significant push back on making this change. But we also have some faculty who very much want it.

Can we make it optional? I was avoiding that approach earlier out of concern about going through the edX review process. But now that they have removed the legacy dashboard altogether, we can make this change without their review -- at least until the eucalyptus release.

@amir-qayyum-khan can you look into adding a checkbox to the legacy dashboard the allows users to optionally make the change that is in @pwilkins's PR https://github.com/edx/edx-platform/pull/10890 (never merged, but we were planning to cherry-pick it into our MITx residential release).

Presumably this would involve a slight change to this block in the view and a corresponding change to this block in the template

[pdpinch]

@pwilkins proposed a UI for making normalization optional. I like the checkbox approach, although it should default to being on (i.e. current behavior).

Ideally, the checkbox should affect the csv download the same as it affects the export to remote gradebook.

[pdpinch]

Peter and I were discussing this on Tuesday and we may need to add an additional column to the csv that is created to indicate whether the grades are on the 0-1 scale or 0-maxpoints scale.