Fixed Django redirect response to allow eid:// protocol

[nils-wisiol]

Not sure if HttpResponseRedirectEId should go into a separate file.

As far as I could tell using frisby, this fixes the eid protocol redirect tests. (Frisby reported the wrong tests to be failing, but with this fix, all tests run just fine.)

The following measures did not fix any tests and did not fix the determination of which tests are failing:

• one test per it
• one it per describe
• using jest rather than jasmine to run the tests
• using jest -i to run the tests sequentially
• fixing an issue where header.location[0] is referenced although sometimes, header.location is undefined (This eases the pain, but frisby's failing test confusion remains.)
• disabling rate limiting in nginx altogether

Note that this PR is against tc_token_url.

Also see #40

[nils-wisiol]

@BenjaminKeller please merge at your discretion

[BenjaminKeller]

@nils-wisiol I tested it locally and it works fine. Travis is also accepting it. Thank you very much!