request to remove --daemon option from xfwm4 invocation

[paciorek]

This option was deprecated and then removed as of [version 4.15.2](version 4.15.2) of xfwm4.

As is, on our OOD instance, our MATLAB app with this xfwm4 invocation doesn't start up the window manager and we see "xfsettingsd: No window manager registered on screen 0." in the OOD output.log file. As a result one can't correctly manipulate the MATLAB GUI window in the app.