Entity: Added IsTNT

git-svn-id: http://mc-server.googlecode.com/svn/trunk@1593 0a769ca7-a7f5-676a-18bf-c427514a06d6
Entity: Added IsTNT
Once again I wasn't paying attention..

git-svn-id: http://mc-server.googlecode.com/svn/trunk@1594 0a769ca7-a7f5-676a-18bf-c427514a06d6