implement login and logout

- add LogoutView to dashboard app
- define logout URL pattern
- only use login view from django.contrib.auth.views instead of including all
  auth URLs
- change base template to support login/logout
- add template dashboard/user_dashboard.html

gnuviechadmin/dashboard/urls.py

@@ -4,6 +4,7 @@ from django.conf.urls import patterns, url
 
 from .views import (
     IndexView,
+    LogoutView,
     UserDashboardView,
 )
 
@@ -13,4 +14,6 @@ urlpatterns = patterns(
     url(r'^$', IndexView.as_view(), name='dashboard'),
     url(r'^user/(?P<slug>[\w0-9@.+-_]+)/$',
         UserDashboardView.as_view(), name='customer_dashboard'),
+    url(r'^logout/',
+        LogoutView.as_view(), name='logout'),
 )