fixed up rule F9.3 (fixmore(), some default fix()-actions, ...)

Created by: jkriege2

This reworks rule F9.3 (http://kicad-pcb.org/libraries/klc/#F9.3) with these features:

• if no model is provided at all: add default model in fix() unless this is a virtual component, which does not always require a 3D model (still all checks are done for virtuals, if models are specified!)
• if errors in 3D model path are there, --fixmore will replace the model path with the default path, which should fix most errors ... exceptions (warning-only), if the model-name starts with the default name, but has an extension (this should capture the e.g. SOT-23_LargePads which should have the same model as SOT-23).

• for the --fixmore i made a default way to require thise fixes also in other rules (simply set self.needsFixMore=True and implement fixmore() ).

What do yout think?

JAN