Monkey patch 'django.utils.translation'

Modify Django's translation library, such that the gettext family of
functions return an empty string when attempting to translate a
falsey value. This overrides the default behavior [0]:
> It is convention with GNU gettext to include meta-data as the
> translation for the empty string.

This patch provides a holistic solution to replace the current piecemeal
approach [1][2].

Affected Methods:
    - gettext
    - gettext_lazy
    - pgettext
    - pgettext_lazy
    - ugettext
    - ugettext_lazy

[0] https://docs.python.org/2.7/library/gettext.html#the-gnutranslations-class
[1] bad803e451ce63b4693ecf52b66cedfce5b43160
[2] https://github.com/edx/edx-platform/pull/4653
I think that if some code is importing like `from django.utils.translation import gettext`, then your monkey-patch won't affect it (because the name `gettext` in the importing module will have already been bound to the unpatched function). However, looking at the structure of the translation module, you could have the affect you want by wrapping the `_trans` object instead (https://github.com/django/django/blob/1.4.8/django/utils/translation/__init__.py#L69). That object is called to do all of the translations by the top level functions. Because of the crazyness that django does here (https://github.com/django/django/blob/1.4.8/django/utils/translation/__init__.py#L66), you'll probably want to override `getattr` yourself, and use that to load up the appropriate attr from `_trans`.