shaded artifacts need to filter jackson 2 service discovery locations

From Sean Busbey comments on HBASE-16338:

the shaded artifacts include incorrect services API definitions for jackson 2 at META-INF/services/ for com.fasterxml.jackson.core.JsonFactory and com.fasterxml.jackson.core.ObjectCodec. They point at classes in their unrelocated state. They should probably just be filtered since things appear to work. It's a relatively harmless nuisance, since if we are loaded into the same JVM as an unrelocated Jackson 2, we point at the same implementation classes as they will. Probably already present before this change, so I'm fine with it getting done in a follow-on.