Fixes and tweaks

• Honda inventory check stopped working because of changes Honda made to their website. Now working again.
• A number of changes to internal logic for handling PC-EFTPOS operations to make the interaction with PC-EFTPOS more resilient.  It appears that sometimes PC-EFTPOS closes the link C9 establishes to it for no apparent reason.  Changes are concerned with ensuring that c9 is better able to cope with these situations
• On one dealer for some reason line margin was calculating line margin on formula costs (stamp duty) when it never should do any such thing. Added changes to c9 to explicitly prevent this from happening.