Remove atstccfg unused code (#3960)
Remove atstccfg unused code (#3960)

Removes code, where remap.config was replacing __HOSTNAME__ in server
parameters, but if you trace thru the code, the only usage
of that data is to check a 'dscp_remap' parameter. The hostname
replacement is totally unused, and at worst, deceptive.
hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol,hbeatty/incubator-trafficcontrol