refactor & unfork as required

[zzkt]

Since there have been a few issues (e.g. #14 and #15) and various complications with the inclusion of the devices interface, I think it could make sense to refactor into "core" and "extras" libraries.

The original intent was to keep the OSC protocol encoding/decoding relatively simple and contained to a single file if possible. The networking layer could be independent. I still think can work, so I've reverted and/or refactored with this in mind.

The core library will remain here and the other-than-core can be found at or near https://github.com/zzkt/osc-devices

core features

• simple functional style interface
• complete protocol coverage
• compatibility with supercollider and pd (at least)
• runs on as many CL implementations as possible
• reasonable error handling & reporting

non-core features

• networking API (c.f. liblo or devices)
• introspection and/or reflection
• etc