Removed a misleading examples from documentations ala ticket #19719
Merge pull request #730 from phantummm/ticket_19719

Fixed #19719 - Removed misleading example from ModelForm documentation
Fixed #19812 - Removed a duplicate phrase in the widget docs.

Thanks diegueus9 for the report and itsallvoodoo for the draft patch.
Fixed #19824 - Corrected the class described for Field.primary_key from IntegerField to AutoField.

Thanks Keryn Knight.
Corrected INSTALLED_APPS syntax in 1.5 release notes.
Merge branch 'master' of http://github.com/django/django