PROTON-214: JNIMessenger now throws ProtonUnsupportedOperation if proton-c functions return failure (non-zero) error codes.
This was done so that proton_tests.messenger.MessengerTest.testSendBogus skips rather than fails when run against proton-jni.

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/trunk@1448962 13f79535-47bb-0310-9956-ffa450edef68