Fix logic … ResponseKey now valid.

./validate.py http://localhost:8888/ws-java-servlet-blocking-rxjava
Validating WsPerfLab Implementation at URL: http://localhost:8888/ws-java-servlet-blocking-rxjava/testA?id=58590

Successful Validation
Now passing validation when run with Jetty 9.1

$ ./validate.py http://localhost:8080/ws-java-servlet-nonblocking-0.1-SNAPSHOT
Validating WsPerfLab Implementation at URL: http://localhost:8080/ws-java-servlet-nonblocking-0.1-SNAPSHOT/testA?id=35761

Successful Validation
Have them all include application/json type