Fix deadlock when indirectly calling PLCObject's evaluator() from twisted of wx event loops. Was freezing while transfer/start/stop through Wamp. Serialize all PLCObject's call to self.PythonRuntimeCall into the same PythonThread thread.
These classes are intended for use server-side.
e.g. in a django view.py :
from pyjs.jsonrpc.django import JSONService, jsonremote
