Babel testcase updates

[j3hyde]

This pull request updates the Flask-Babel testcase for datetime formatting with expected values that match the locale settings in Babel.

For example, leaving Flask-Babel out of things:

>>> from babel.core import Locale
>>> l = Locale.parse('de_DE')
>>> l.datetime_formats.items()
[(u'medium', u'{1}, {0}'), (u'long', u"{1} 'um' {0}"), (u'full', u"{1} 'um' {0}"), (u'short', u'{1}, {0}')]

Flask-Babel's current testcase expects formats without the 'um' and ',' so this pull request adds them in.

[TkTech]

:+1: