Added MessageDecoder interface. All decoder implement this.

Added DecoderFactory. This creates an appropriate decoder based on a MessageType.
BoatActionDecoder implements MessageDecoder.
BoatLocationDecoder implements MessageDecoder.
HeartBeatDecoder implements MessageDecoder.
JoinAcceptance implements MessageDecoder.
RaceStatusDecoder implements MessageDecoder.
RequestToJoinDecoder implements MessageDecoder.
XMLMessageDecoder implements MessageDecoder.
Refactored CourseWind decoder/encoder. CourseWind decoder/encoder is for an individual CourseWind.
CourseWinds decoder/encoder is for the combined message from the API.
Documented BoatAction, and it now contains a BoatActionEnum instead of a byte.
Refactored CourseWind and CourseWinds classes. They now expose correct units, instead of packed units.
Added CourseWindDecoderTest, and updated CourseWindsDecoderTest.
issue #35 #36
#story[1095]

racevisionGame/src/main/java/network/MessageDecoders/MessageDecoder.java

@@ -0,0 +1,21 @@
+package network.MessageDecoders;
+
+
+import network.Messages.AC35Data;
+
+
+/**
+ * This is the interface that all message decoders must implement.
+ * It allows for {@link #decode(byte[])}ing messages.
+ */
+public interface MessageDecoder {
+
+
+    /**
+     * Decodes a given message.
+     * @param encodedMessage The message to decode.
+     * @return The decoded message.
+     */
+    public AC35Data decode(byte[] encodedMessage);
+
+}