SCP: Fix NOEXPECT to actually delete a single indicated expect rule.  Allow expect actions to be provided.  Fix match buffer management when expect regular expressions are in use.
SCP: Fix help text for expect command.
SCP: Fix SEND <dev>:line when after=nn and delay=nn not specified

For a command like:  SEND MUX:0 "abc"
in which a device is specified but there are no after=nn and delay=nn parameters, the code neglected to update cptr, resulting in an illegal argument error condition.
SCP: Added const declarations to various APIs to reflect the appropriate usage.  Moved parameter values for run_cmd and exdep_cmd to scp.h
SCP: Added a Remote Console Master Mode.

This capability will allow a GDB RSB stub to be created to support dynamic debugging of code running in a simulator.

This capability will also allow a complete front panel emulation system to operate a simulator.

This capability is engaged in a simulator by:
     sim> set remote telnet=remoteconsoleport#
     sim> set console telnet=consoleport#
     sim> set remote master

Master mode will provide a TCP session which accepts SCP commands that allow full control of the simulator.
SCP: Cleanup minor remote console behaviors (stutter prompt and broken single mode command)
Compiler suggested cleanups - mostly const fixups