E-mail date header should be in the local time zone

[geofft]

Outgoing e-mails should use the time zone of the application instead of hardcoding UTC-0. In addition to generally making more sense for servers outside England, my e-mail client (alpine) happens to display the time in the index view without converting it to local time. Fortunately, using the local time zone is easy:

>>> email.Utils.formatdate()
'Fri, 14 May 2010 06:38:42 -0000'
>>> email.Utils.formatdate(localtime=True)
'Fri, 14 May 2010 02:39:33 -0400'

I've attached a patch to django.core.mail.message to effect this.

[geofft]

Call formatdate with localtime=True.

[Ramiro Morales]

Duplicate of #12666.