Investigate installing our own Python on Windows, or at least creating our own venv

[jackjansen]

The dependency on the System Python is too cumbersome and error-prone.

But the problem is that that will forestall using cwipc for things like point cloud analysis, or at least make it a lot more difficult.

[jackjansen]

Turns out it was easy: we create a venv in libexec/cwipc in which we install the cwipc modules, and then we copy the executables from there over into our bin directory.

And if people want to install the cwipc package into another venv (or another Python, or whatever) they can simply run cwipc_pymodules_install with whatever Python they want and also have everything available there.