Convert cli.SubmitOpCode to use the master

This patch converts the cli.py SubmitOpCode method to use the unix
protocol and thus execute the opcodes via the master.

The patch allows a partial burnin to work with the master. Currently the
query opcodes, since they are executed via the SubmitOpCode, are
executed inside a job too, which is suboptimal, but they work fine.

The cmd lock has been removed from the master, but the cli.py still
takes the lock. This is ok for this in-progress patch (since the master
still has only one executor thread). This will be fixed in a future
patch.

Reviewed-by: ultrotter