Improved and enhanced the floppy emulation

[fysnet]

This improves and enhances the floppy emulation.
This adds the ability to specify a controller type.
This adds all but one, known, controller command.
This fixes the format command. Issue #123
This fixes the error with older Windows guests.

[stlintel]

Volker, Ben - what is the testing / level of confidence needed to merge it ?
I am not a person to decide here, can only approve and merge when ready

[stlintel]

BTW, Ben - do you have access to 'Squash and merge' button ?

[fysnet]

Volker, Ben - what is the testing / level of confidence needed to merge it ? I am not a person to decide here, can only approve and merge when ready

I tested all floppy sizes with DOS and FreeDOS, most sizes with Win98 and Win2k, and all sizes above 360k with WinXP. I know the that Scan functions may or may not be correct, though I have no way of testing them other than my own code. I know of no Guest that supports these functions. Every physical hardware I tested with, even though the specifications say the Scan functions are supported with that hardware, return "illegal command".

It would be good if Volker can make a few tests too (please), but I feel confident to merge.

BTW, Ben - do you have access to 'Squash and merge' button ?

I do not have access to either. It still says:

Only those with write access to this repository can merge pull requests.

Thanks,
Ben

[fysnet]

I added a few very minor fixes and cleanups. This should be it, ready for merging. Thanks.