Motivation:
Enables optional .startsWith() matching of req.uri() with websocketPath.
Modifications:
New checkStartsWith boolean option with default false value added to both WebSocketServerProtocolHandler and WebSocketServerProtocolHandshakeHandler. req.uri() matching is based on this option.
Result:
By default old behavior matching via .equal() is preserved. To use checkStartsWith use constructor shortcut: new WebSocketServerProtocolHandler(websocketPath, true) or fill this flag on full form of constructor among other options.