It seems like usc-features has a dependency on usc-agent that is not explicitly declared.

Error resolving artifact org.opendaylight.usc:usc-agent:jar:1.0-Daily: Could not find artifact org.opendaylight.usc:usc-agent:jar:1.0-Daily in central (http://repo1.maven.org/maven2/)

I believe the fix should be to add usc-agent usc-features (unless another bundle should be pulling it in).