Make data logging optional (internal)

If the recorder is initialized with a filename, write trace data
to that file.  But if it is not initialized, don't complain and
don't write the data anywhere.
simulator: cmdline switches for output options

Teach simulator several command line options to control console output
of info messages, gcode traces, data_recorder output, etc.

Also move gcode output to sim_gcode instead of sending directly to
datarecorder.