Static with class definition fix.

[sampottinger]

Closes #579:

It looks like Processing 3 was a bit more eager to try to put the user in static mode. I’m not 100% sure but I think this might have accidentally caused some undesired wrapping previously. Regardless, I replicate the 3x behavior while still supporting Java mode by:

• Try matching static mode before Java mode.
• If there is ambiguity, check for main in the root object provided by the user.
• Check if the user is trying to import processing core manually and avoid double import of automatic includes.

This PR adds tests both from #579 and also a new test where the mode is ambiguous but root object includes a main method.

[sampottinger]

I think this is ready for you @benfry!

[sampottinger]

… Just to be sure, quick checked this on a fresh linux machine and it worked!

[benfry]

Thanks!