ACCUMULO-1323 fixed prompting for password in shell and added some option checks for user, password, and token options.

git-svn-id: https://svn.apache.org/repos/asf/accumulo/branches/1.5@1469629 13f79535-47bb-0310-9956-ffa450edef68
ACCUMULO-1323 fixed prompting for password in shell and added some option checks for user, password, and token options.

git-svn-id: https://svn.apache.org/repos/asf/accumulo/trunk@1469630 13f79535-47bb-0310-9956-ffa450edef68