Some minor fixes, simplifications and improvements.
In detail:
* create valid Python code
* allow creating a Python class also without a Qt package
* hint about the need for a Qt package depending on the
base class
* remove QDeclarativeItem as base class as this is not
present in recent Qt packages
Change-Id: I7198f315b3a9eec9a04f52d7438d05ccce40c3f7
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>
Reviewed-by: David Schulz <david.schulz@qt.io>