Add a parameter to tell daqd_shmem when it is a gds broadcaster.

set parameter "GDS_BROADCAST" = "1"; for a gds broadcaster.

git-svn-id: https://redoubt.ligo-wa.caltech.edu/svn/advLigoRTS/trunk@4759 6dcd42c9-f523-4c6d-aada-af552506706e