Module SDK and dynamic loading

[schrnz]

We want to be able to write modules without requiring to compile them with/into the compiler and load them dynamically.

One possible approach is to create a module sdk that is used to create and compile modules as regular c++ projects without the need to ever touch the compiler. The idea is that the resulting compiled module registers itself with the compiler so that we can not only control externally which of the modules in the compiler are executed (see #4 ) but actually move the module code out of the compiler and only have module-agnostic code in there.

There are multiple advantages:

1. Developing modules does NOT require building (in the context of) AOSP anymore, which lowers the gap to use artist tremendously.
2. We can load or unload modules from the GUI (see also API for controlling modules from outside the compiler #4)
3. Modules can be separate projects and do not bloat the ARTist codebase.

[schrnz]

moved to Project-ARTist/meta#3