Implemented static packet header length defined in DropOSProtocol class
Attempting to place file size on the first byte.
Doesn't bother with sending a "GO" message.
Does not include header packet as payload.
Can send files as one bytestream as packet header and payload.
See DropOSProtocol.sendHeaderAndFile() method.
Read only this amount of bytes when receiving files.
Fixed: disordered flushing / closing.
Renamed DropServer to ConnectionHandler.
Renamed ClientConnection to DropServer.
Placed IOExceptions to be handled by main thread.
DropServer class now has ADD, MODIFY, and DELETE private methods.
Sockets created in eventPerformed(). addFile() now throws the exception
to be handled in eventPerformed().
Null check.
Comments on the DropClient.
Renamed DirectoryEvent to SynchronizationEvent.
Removed unnecessary imports.
Merge branch 'master' of https://github.com/addicteduser/CSC611M-DropOS

Conflicts:
	CSC611M Simple File Sharing/src/dropos/ClientConnection.java
	CSC611M Simple File Sharing/src/dropos/DropClient.java
	CSC611M Simple File Sharing/src/dropos/DropServer.java