formalize openmrs-core coding rules and style

[mogoodrich (Mark Goodrich)]

Thanks for doing this @teleivo!

I just make some comments in on alerts and the rules themselves in another thread:

Codacy Bot comments?

Cool to see codacy running, but anyone know if there’s a way to set Github so a particular user’s comments (in this case the codacy-bot) doesn’t trigger a message to “watchers”. I’m watching OpenMRS Trunk, and would be nice if I could keep watching it, but I’m going to stop watching if it means getting 10 emails in a row when the codacy-bot runs… Also, looking deeper, we are probably going to want to tweak the rules a bit… having all methods under 75 lines is probably ideally …