assignment_tag deprecated in Django 1.9

[chrisroker0]

@register.assignment_tag causes error on runserver

Changed :

def social_get_facebook_locale(locale):
    """
     Normalize the locale string and split the value needed for the api url
    """
    if locale is None:
        return 'en_US'

    return normalize(locale).split('.')[0]

To:

@register.simple_tag
def social_get_facebook_locale(locale):
    """
     Normalize the locale string and split the value needed for the api url
    """
    if locale is None:
        return 'en_US'

    return normalize(locale).split('.')[0]