Remove workaround for django <1.0

It's not entirely clear to me that the module is used at all; it seems to
duplicate functionality in the ESPErrorMiddleware, but this part is definitely
not used any more; it was last needed in pre-1.0 versions of django circa 2007.
Remove old email verify module

It had no @main_call or @aux_call, nor even a method with the right signature;
the method that appeared to be intended as its @main_call contained undefined
names, it didn't even exist as a ProgramModule in the esp.mit.edu database.
The code does not appear to have been nontrivially touched since at least 2007.
Merge pull request #1506 from learning-unlimited/dead-code

Remove more dead code