P3IO and EXTIO drivers, ddrio-p3io implementation

[icex2]

The goal of this contribution is to have a ddrio-p3io implementation that allows owners of DDR SD cabinets to run the P3IO DDR (Dragon) + EXTIO hardware combination through bemanitools's ddrio API.

As a "byproduct", this also adds:

• p3iodrv: A library to drive real P3IO DDR hardware from a Windows host
• extiodrv: A library to drive real EXTIO hardware from a Windows host
• extiotest: Small CLI testing tool to test real EXTIO hardware connected to a Windows host
• ddriotest: Testing tool for ddrio API implementations
• p3io-ddr-tool: Extensive CLI testing tool to test and debug a P3IO + EXTIO DDR SD cabinet hardware setup

Note that not all features of a P3IO and EXTIO are currently supported. However, all features required to implement a fully functional ddrio API library are supported in order to operate the cabinet fully with all inputs and (light) outputs.

For individual details, refer to the separate commits.

[icex2]

Decided to move forward with this because it appears difficult to get this tested in isolation before a release. Will point out that out in the next release and going for forward fixing. Naturally, prior releases can be used as fallbacks on unexpected new bugs being introduced by this.