Chat DX commands to allow chat customization

With these changes #316 is closed. 

Commands added are 

!chat - Various commands to manipulate the chat window
!chat dragwindow <true|false> - Makes the chat draggable
!chat offsetting <true|false> - Turn on/off the tracking center and editor offsets
!chat offset [tracking|editor] [offsetX] [offsetY] - Set the offset values (pixels)
!chat [width|height|top|left] [value] <percent|pixels>

The server messages now also have the black border.