Use enum for state

git-svn-id: https://svn.apache.org/repos/asf/jmeter/trunk@1544804 13f79535-47bb-0310-9956-ffa450edef68
Add a warning if deprecated property is used

git-svn-id: https://svn.apache.org/repos/asf/jmeter/trunk@1544805 13f79535-47bb-0310-9956-ffa450edef68