The hadoop-common pom currently has a dependency on kerb-simplekdc. In
fact, the only classes used from Kerby are in kerb-core and kerb-util
(which is a transitive dependency frmo kerb-core). Depending on
kerb-simplekdc pulls a bunch of other unnecessary classes into the
hadoop-common classpath.
This changes the hadoop-common pom to depend only on kerb-core.
hadoop-minikdc already had the appropriate dependency on kerb-simplekdc
so it continues to pull in what it needs.
Signed-off-by: Todd Lipcon <todd@apache.org>