Process TCP-based Variables commands

Process most commands and place results in appropriate queues, but so far
nothing is actually done with those queues.  That is next on the
implementation.  All commands read in as expected, and the few that aren't
supported respond as such.

CC (Close Connection) command is missing, need to decide the best way to
handle that particular case.
Moved all TCP interface to subdirectory

Tried to better organize by moving the higher-level TCP interface commands
to their own subdirectory.
Fix TCP Timeout defaults (0->25s) and error clear

Defaults were at 0s for timeout, resulting in no command ever being
accepted.  Fixed this for all functions that read in values from the TCP
connection.

Also, timeouts were handled properly by the initial command reader, but
were being cleared by subsequent call to TCP Flush inside the command
handler's "BC" case.  Fixed this by fencing it with a Error-No Error case
structure at the input, so the timeout will never be cleared if there is
already a timeout when it is called.
Process TCP-generated variable sets

codes/Utils/ExternalFeedback/LoadVarSetIntoVM.vi provides the interface
for the individual variable sets to get updated in the variable manager.

SetList.vi was modified to incorporate both the "Update Now" options (via
a while loop on a short delay as in the Mulligan functionality) and the
"Update after Sequence" option (via a persistent queue that is checked for
items once the Sequence History Table is filled with "Complete").

Currently will not automatically start a sequence if it was idle and a set
is added for "after sequence".

Currently will not look at the "After Sequence" queue at all if in cycle
mode, I don't think.
Add Python example TCP client for Variable FB

A rough python client that can generate and send sets of variable over TCP
successfully.  Used in testing that functionality.