Client-Server communcation protocol

[tbrockman]

Features

- [x] Add an additional part in the protocol where the server sends newly connected clients the song queue

• Fix bug where queue immediately plays next song upon sending to new clients
• Paginate the queue returned, scroll to request more from server AND/OR remove sending of album art from server to clients when sending "add" event
• Include a start-up message from server to client sending the currently playing song information, including songs current play time
• Implement pause and resume messages for currently playing state changes
• Remove sending any album art from either server or client, can't trust that images sent from either side are correct and leads to sending more data than necessary.
• Improve protocol to include password verification on initiation