added django-uni-form to requirements

docs/installation.rst

@@ -22,6 +22,15 @@ Installation
 Dependencies
 ------------
 
+django-uni-form_
+^^^^^^^^^^^^^^^^
+
+This is semi-optional as the only reason it is required is the included
+`_invite_form.html` renders the form through the `as_uni_form` filter. If
+you override this template in your project, you obviously remove this
+requirement at least in context of this app.
+
+
 django-email-confirmation_
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
@@ -34,5 +43,6 @@ pinax.apps.signup_codes_
 Used to manage the sending and processing of signup codes via email.
 
 
+.. _django-uni-form: https://github.com/pydanny/django-uni-form
 .. _django-email-confirmation: http://github.com/pinax/django-email-confirmation
 .. _pinax.apps.signup_codes: http://github.com/pinax/pinax