2.0.x traffic router will not build

traffic_router (in 2.0.x branch only!!) build fails with this error:

```Downloading: https://repo.maven.apache.org/maven2/com/comcast/cdn/traffic_control/traffic_router/traffic_router/2.0..0/traffic_router-2.0..0.pom
^M[ERROR] [ERROR] Some problems were encountered while processing the POMs:
[FATAL] Non-resolvable parent POM for com.comcast.cdn.traffic_control.traffic_router:traffic_router_rpm:[unknown-version]: Could not find artifact com.comcast.cdn.traffic_control.traffic_router:traffic_router:pom:2.0..0 in central (https://repo.maven.apache.org/maven2) and 'parent.relativePath' points at wrong local POM @ line 22, column 10
@
[ERROR] The build could not read 1 project -> [Help 1]
[ERROR]
[ERROR] The project com.comcast.cdn.traffic_control.traffic_router:traffic_router_rpm:[unknown-version] (/opt/incubator-trafficcontrol/traffic_router/build/pom.xml) has 1 error
[ERROR] Non-resolvable parent POM for com.comcast.cdn.traffic_control.traffic_router:traffic_router_rpm:[unknown-version]: Could not find artifact com.comcast.cdn.traffic_control.traffic_router:traffic_router:pom:2.0..0 in central (https://repo.maven.apache.org/maven2) and 'parent.relativePath' points at wrong local POM @ line 22, column 10 -> [Help 2]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
/incubator-trafficcontrol/traffic_monitor/target/rpm/traffic_monitor/tmp-buildroot/opt /incubator-trafficcontrol/traffic_monitor/target/rpm/traffic_monitor/tmp-buildroot/var /incubator-trafficcontrol/traffic_monitor/target/rpm/traffic_monitor/buildroot```