During testing of the NVRAM Switch changes (#451), I found some pre-existing stuff I didn't like, so I have tried to clean things up.
- BOOT_DEFAULT has been replaced by AUTO_CMD
- There is no longer a "default" boot loader command when pressing <enter>.
- Detect CTS at startup to ensure it is asserted. If not, disable hardware flow control to avoid stalling the console at boot. Only for UART driver because this is the only place it is currently relevant.
The EtchedPixels floppy disk controller is known by the identifier
'FDMODE_EPFDC', but the comments in the Config subdirectory have an
incorrect reference to 'EPWDC'. This fix updates the comments to use the
correct name.
