Fix avro conflict for hadoop1 and hadoop2.

This moves the avro dependency _above_ the hive dependencies in the
kite-data-hcatalog pom because hive-exec includes avro classes (Schema)
and is the cause of a java.lang.VerifyError. Moving the dependency
causes the constructed classpath to search the avro jar first.

All modules that pull in hive-exec transitively now have avro listed as
the first dependency.