UDR (Unifi Dream Router) and UDM (Unifi Dream Machine) holder

This is a reinforced version of UDM mount by Revnull. Who's desighn while elagent and well desighned is lacking structulary. So to prevent a repeat of the brackets snapping i have redisghned it to have quater circle reinforcemnets up each bracket this should serve to solve the problem. 

I have also moved the screw holes because my particular use case required them shifted by a about 5m. I have kept the traks for double sided tape if required.

V1.3 fixes 2 problems a slight gap in the support and the lack of two holes