Include module name in the fact docs, fix fact reference on doc index.

Author: Fizzadar

docs/index.rst

@@ -38,7 +38,7 @@ Deploy Reference
 
 .. compound::
     :doc:`facts`
-        A list of all facts ``pyinfra`` can gather from hosts, e.g. ``host.fact.os``.
+        A list of all facts ``pyinfra`` can gather from hosts, e.g. ``server.Hostname``.
 
 .. compound::
     :doc:`examples`

scripts/generate_facts_docs.py

@@ -79,7 +79,7 @@ def build_facts():
                         if arg != 'self'
                     ))
 
-            title = ':code:`{0}`'.format(name)
+            title = ':code:`{0}.{1}`'.format(module_name, name)
             lines.append(title)
 
             # Underline name with -'s for title