Initial NVRAM Changes,

[kiwisincebirth]

Initial NVRAM Changes, for HBIOS including public API, sysconfig app, build changes

The HBIOS code is developed (functional) and somewhat tested. It posesses

1. An new section in HCB ($30) containing the data
2. SYSGET and SYSSET routines
3. Routines to read and write HCB to NVRAM
4. Initialisation logic called once on boot
5. 1 byte Parity check using XOR, calc includes Header,Data,Version

As well as this

1. Definitions for 2 Switches relating to Auto Boot
2. A ROM application which also builds a CP/M application
   that maintains the 2 switches

[kiwisincebirth]

@wwarthen - I would appreciate a good look over this

[wwarthen]

I see no immediate issues. See comments in Issue #451.

I will need to make a few minor adjustments to ensure this builds in all build environments. I will take care of this shortly with a follow-up check-in.

I have not entirely finished reviewing the code, but it is easier for me to proceed at this point by merging and then continuing to test.

Thanks! Wayne