MockOutput now uses LatestMessages for xml messages.
Moved xml message encoding into RaceVisionByteEncoder. Removed XMLMessageEncoder.
Moved XML message sub types into an enumeration (XMLMessageType).
XMLMessage can now be queried for its attributes (like timestamp, length, etc...).
VisualiserInput now uses LatestMessages.
VisualiserInput now (as it did previously) uses switch statements for checking packet type, instead of if statements.
VisualiserRace now uses LatestMessages instead of VisualiserInput.