ACCUMULO-581 added test for shell trace command

git-svn-id: https://svn.apache.org/repos/asf/accumulo/branches/1.5@1459752 13f79535-47bb-0310-9956-ffa450edef68
ACCUMULO-581 wait longer for traces to flush out

git-svn-id: https://svn.apache.org/repos/asf/accumulo/branches/1.5@1459765 13f79535-47bb-0310-9956-ffa450edef68
ACCUMULO-581 wait longer for traces to flush out

git-svn-id: https://svn.apache.org/repos/asf/accumulo/trunk@1459766 13f79535-47bb-0310-9956-ffa450edef68