[vcf-midatlantic] RASCSI scsi emulator device

[Andrew Diller]

Reading over these RASCSI devices, I decided to pick up one to see how it works with some other classic UNIX systems, where I'm currently using a SCSISD (SGI, DEC and AUX). The performance seems to be a nice boost when used with Pi4.

https://github.com/akuker/RASCSI/wiki/Benchmarks

It will be nice to have an intelligent alternative to the SCSISD.

This device reminds me of DavidG's wonderful MFM emulator. I'm hoping that with access to a real PI doing things like imaging of drives will be much easier than it currently is.

-andy