Allow specifying a character code which, upon receipt, will reboot system. Only useful/implemented for interrupt driven serial drivers. Currently only implemented for ASCI and SIO. Do *not* use this unless you fully understand the ramifications!!!
- New Z280 bank selection routine that does not require gigantic table and is about as fast.
- Bump Z280 UART driver to 128 byte buffer.
- Truncate unused portion of Z280 IVT at end.
- Complete initial support for Karl's Z280 module w/ 512K RAM/ROM module
- Allow swapping Z180 serial ports via ASCISWAP config variable
- Fix Z180 include file per Issue #141 from J.B. Lang
- Updates DEVICE call for all CIO devices to return unit mode and I/O base address
- Improved experimental XModem (XMX.COM) that uses direct hardware I/O for UART and USB-FIFO devices
