Changes to live listener end-of-run processing

Two changes:
1) Return true from the rxpacket() function when we receive an END_RUN
status so that we'll break our of the packet receive loop
2) Properly re-initialize the workspace at the start of the next run

Refs #6365
Change handling of initial run_start value in live listener

We need a value for the run_start property regardless of whether or not
we're actually in a run.  We'll get it from the Run Status packet, which
is guaranteed to be the second packet we receive when we connect to SMS.

Refs #6365