Allow Importing of CSV Files To Plan

[AdrianSantoPasqualini]

UPDATE: This feature was replaced by the Auth system. I am keeping this PR around in case we still want to add something like this later.

Adds a new tab which gives a brief explanation to the user and lets them upload csv files.

The courses will be read from the csv and added to the plan.

[kevinfwl]

Do we need to assume that the user doesn't change majors? I am getting this by:

1. Selecting actsci
2. Downloading actsci csv
3. Selecting general science
4. Apply actsci csv

[kevinfwl]

Also am getting these duplicates, is this expected as well?

[AdrianSantoPasqualini]

Do we need to assume that the user doesn't change majors? I am getting this by:

1. Selecting actsci
2. Downloading actsci csv
3. Selecting general science
4. Apply actsci csv

Are the course cards that got added working correctly?

[AdrianSantoPasqualini]

Also am getting these duplicates, is this expected as well?

Duplicates are expected, all the import is doing is taking the courses from the csv and adding them to the plan, The csv doesnt have any information about what underlying choices resulted in those courses, so I cant remove them from the requirement bar.

Perhaps I should give more detail as to how the import works in the tab description

[kevinfwl]

Yeah I think everything is working correctly functionality-wise other than those two; adding an explanation to the import page should be good.

[haowei99]

What are we doing with this?

[haowei99]

Tested, CSS looks really clean!

I noticed the background color of the sign out button isn't the same as the add courses (it is actually #f5f5f5, not white). I have already pushed a commit to address this.

Good to merge to prod. @b47huang Please take a look at it as the last pair of eyes.