- Add missing Django 1.6's earliest method.
- Fix passing None to TranslationQueryset.latest.
- Make create_bulk raise a NotImplementedError instead of breaking.
Make decorators to skip tests on older or newer django versions.
Added Italian translation
Merge pull request #178 from Madec/master

Add Italian messages.
Removed _real_manager and _fallback_manager indirections as they were confusing and served no real purpose.
Made all 3 querysets used by TranslationManager customizable (translated, untranslated, default)
Reworked TranslationQueryset so its constructor takes the standard arguments again.
Add tests for FallbackQueryset
Allow passing None as one of the fallbacks - None will be replaced with current language at query time.
Change fallbacksqueryset to use a self join instead of multiple queries on Django 1.6+