Email Notifications Implementation

The manage command notifysendemails is implemented. The command forks a process that can be daemonized and starts sending the emails to subscribed users taking into account the interval subscriptions.

The commit contains a dummy backend.
Revert "Email Notifications Implementation"

This reverts commit 700bb6e90fa316ed02c7e5d2db270dfaf54da17c.
 Notifications Implementation:

The manage command notifysendemails is implemented. The command forks a process that can be daemonized and starts sending the emails to subscribed users taking into account the interval subscriptions.
The commit contains a dummy backend.
Subject changed to a translated string, notification email changed to @example.com
Merge pull request #115 from jdcaballero/master

django-notify email notifications