Refactor tests

 * Use standard django structure for tests.
 * Update test implementation.
Prefix keys used in admin to avoid conflicts.

 * Prefix context variables and query keys with 'ml_' to avoid possible conflicts with other applications.
Add changelog
Fix model admin views

 * Fixup 059bd86, change prefix in admin to `ml_admin_`.
 * Rewrite admin tests, use client.
Merge branch 'master' of github.com:vzima/django-multilingual-ds9 into vzima

Conflicts:
	multilingual/admin/options.py
	multilingual/tests/core/models.py
	multilingual/tests/core/tests.py
Updated version to 0.3.0.7