Create a USB bulk transport implementation suitable for SIMH use

[ChrisPVille]

USB Mass storage does not support passing the types of error information various OSes like RT-11 and RSX-11 need in order to work fully with the RL02.

The RL02 disk packs pretty much all had bad sectors somewhere. These can be identified and stored in a factory provided table on the last track of the disk, but it was up to each OS to decide how to handle them. Some skip sectors while others remap them.

Implement an advanced mode over bulk transport which exposes the underlying error bits and drive state to SIMH. (SIMH will require a driver, which is a separate repo).