binary message decoder as well as refactor of xml encoder and decoder placement

-added binary message decoder

#story[782]

src/test/java/XMLMessageDecoderTest.java

@@ -1,7 +1,7 @@
 import org.junit.Assert;
 import org.junit.Test;
-import seng302.XMLMessageDecoder;
-import seng302.XMLMessageEncoder;
+import seng302.Networking.XMLMessageDecoder;
+import seng302.Networking.XMLMessageEncoder;
 
 import java.io.BufferedReader;
 import java.io.IOException;

src/test/java/XMLMessageEncoderTest.java

@@ -1,6 +1,6 @@
 import org.junit.Assert;
 import org.junit.Test;
-import seng302.XMLMessageEncoder;
+import seng302.Networking.XMLMessageEncoder;
 
 import java.io.*;