DX7 namespace proposal and tests

DX7 namespace proposal and tests

An initial attempt at a namespace for the Yamaha DX7 is attached. I started by drawing up a UML class diagram, and derived the OSC address space from it. This is a proposed as a possible direction for Integra, i.e. we define an abstract module hierarchy, which describes module interfaces and derive other things (module implementations, OSC addresses) from it. The classes towards the top of the tree are temporary placeholders until they have been properly defined. There are also some PD patches that attempt to implement some classes, and an inheritance mechanism in PD. IMO it is quite clunky, but some aspects of it may be of interest. A more in depth feasibility study will be made available shortly.