Implemented bulk email interface for new dashboard

Responses to Adam's comments; reset common.py, i18n compliance, deleted extraneous email.html file, fixed an HttpResponse, deleted unnecessary commented-out code, some small style tweaks
added self to authors style, changed GET to POST
Added acceptance tests for bulk email (through beta dashboard)
Merged in email confirmation modal
100% coverage aww yiss
Green notification message now works
added self to authors style, changed GET to POST
Added acceptance tests for bulk email (through beta dashboard)
100% coverage aww yiss
fixed indent + changelog