Fixed one typo in response_helpers which caused is_admin context variable not to work correctly. Created new checkLinkNameForId function that checks if link_name is correct when creating new user and modifying existing one. This is now used for validation instead of doesLinkNameBelongToId in UserForm clean_link_name function. The previous validation function didn't allow to create new users and modify linkname of existing ones. Additionally I created new doesLinkNameExist helper function.

from django.conf.urls.defaults import *

urlpatterns = patterns('',
    (r'^$', 'examples.views.index'),
    (r'^hello/', include('examples.hello.urls')),
)