Protect shared palette and state buffer with a mutex.  Remove defunct spltty() calls while I am here.
Protect shared palette and state buffer with a mutex.  Remove defunct
spltty() calls while I am here.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase