UNDERTOW-1521 test case (based on ssltest)

There are two .java source files which contain everything. You can use Apache ant or the build.sh script to compile the .java source and bundle it into an executable JAR file, which an be run like this:

$ java -jar ssltest.jar -connectonly TARGET_UNDERTOW_SERVER_NAME_OR_IP:TARGET_PORT

The hostname of the target server is required, and the default port is 443 (HTTPS).