ACCUMULO-1421 use reflection to work around class/interface change in Counter

git-svn-id: https://svn.apache.org/repos/asf/accumulo/branches/1.5@1484908 13f79535-47bb-0310-9956-ffa450edef68
ACCUMULO-1421 use reflection to work around class/interface change in Counter

git-svn-id: https://svn.apache.org/repos/asf/accumulo/trunk@1484917 13f79535-47bb-0310-9956-ffa450edef68