Small changes and NES support!

Hi all, I have updated Pas6502 again; main with some very minimal NES support with a couple of working examples :)
There are some caveats with using the NES right now:

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NOTE: The NES target has some programming limitations due to the current compiler design (no routine parameters/local vars on stack yet):

• Routines must have no formal parameters, or only have pure assembly parameters.
• Can’t use local variables in the routines, must use global variables.
• Some internal routines (for mul/mod/div mainly) use parameters in functions/procedures and might not work properly due to being compiled in ROM.

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