add better error reporting in drcargs when director-config is not set
add better error reporting in drcargs when director-config is not set

patmarion/director,manuelli/director,openhumanoids/director,manuelli/director,openhumanoids/director,openhumanoids/director,mitdrc/director,patmarion/director,mitdrc/director,manuelli/director,patmarion/director,mitdrc/director,mitdrc/director,mitdrc/director,openhumanoids/director,patmarion/director,manuelli/director,openhumanoids/director,manuelli/director,patmarion/director