Refactor aposmm_localopt_support for windows/spawn support

[jlnav]

• With gen_funcs.rc on windows, write/read localopt methods from file to avoid None
• Performance study

[jlnav]

aposmm_localopt_support doesn't necessarily need to be refactored! a better solution in gen_funcs/__init__.py was found. So the old approach of imports happening at the top of aposmm_localopt_support is staying, so a performance study may not be needed?

[jlnav]

Closed by #891