Refactored XMLMessageDecoder to be consistent with other decoders - only needs to expose the XMLMessage.
Refactored BoatLocationDecoder to be consistent with other decoders - only needs to expose the BoatLocation.
Updated XMLMessageDecoderTest to use new encoder/decoder. Also tests all three message types.
Removed XMLMessageEncoderTest as it was redundant.
Updated BinaryMessageDecoderTest.xmlMessageTest() to use updated XMLMessage encoder/decoder.
issue #35#36
#story[1095]
fjc40