Add django-i18n to the mailing lists documentation

[Baptiste Mispelon]

The page for Django's official mailing lists (​https://docs.djangoproject.com/en/1.6/internals/mailing-lists/) should mention the django-i18n mailing list, used to discuss internationalization of Django's components.

From a quick search, that mailing list is only mentionned on the "Localizing Django" page (​https://docs.djangoproject.com/en/dev/internals/contributing/localizing/#translations).

Additionally, the link to the mailing list on that page is broken and should be fixed too.

[ANUBHAV JOSHI]

I have added a patch: ​https://github.com/django/django/pull/2443
And link on translation page is good.

[Tim Graham <timograham@…>]

In 0399523cf1ac1f6adcfe593e05824ff4f98da3d3:

Fixed #22253 -- Added django-i18n to the mailing lists docs.

Thanks bmispelon for the suggestion.

[Tim Graham <timograham@…>]

In a01daaf2319ecb2361cc3ecbe872c4fb7fc4817f:

[1.6.x] Fixed #22253 -- Added django-i18n to the mailing lists docs.

Thanks bmispelon for the suggestion.

Backport of 0399523cf1ac1f6adcfe593e05824ff4f98da3d3 from master