ACCUMULO-1438 update usage to "minicluster"

git-svn-id: https://svn.apache.org/repos/asf/accumulo/trunk@1486136 13f79535-47bb-0310-9956-ffa450edef68
ACCUMULO-118 merge trunk to branch

git-svn-id: https://svn.apache.org/repos/asf/accumulo/branches/ACCUMULO-118@1486203 13f79535-47bb-0310-9956-ffa450edef68