Added support for outbound message fragmentation in binary
LargeCommands.java:
-sends a large block of binary data (80 bytes) after sending large text command

MessageCenter.java:
-added sendMessageFragment() to handle both binary and text fragments
-implemented sendBinary() and sendBinaryFragment()
-sendCommandFragment() moved most functionality to sendMessageFragment() to keep code small
-removed duplicate START_BYTE from MessageCenter
-moved MAX_DATA_SIZE to Message class