Deploying SDK runtime components

[markfinal]

So the use case for this is the Python SDK at the moment.

The SDK has header files and libraries to compile and link against for embedding an interpreter.
But, it also has runtime components, such as the Python shell executable, and Python scripts and plugins that make up the standard distribution.

For a simple test case, you might want to deploy the Python shell with the standard library + plugins, and some test data.

For a more complicated case, you might want to compile against the headers and link against the libraries, deploy the standard library + plugins, for an embedded interpreter. The shell executable is not needed now.

How does a Publishing step request this? And how does an SDK expose it?