Introduce property for setting a connection timeout to the client side API

When using the JSR356 WebSocket Client side API to connect to a server:

javax.websocket.WebSocketContainer.connectToServer(...)

there is no way to specify a connection timeout. The method connectToServer() will block until it establishes a connection (which may never happen).

Some implementations (Tyrus, Jetty) provide their own specific ways to do this, but the spec does not.
#### Affected Versions
[1.1]

Start with the JSR356 WebSocket Client API, especially the WebSocketContainer.connectToServer(...) methods, and compare the client-side timeout approaches mentioned for Tyrus and Jetty. Done means the specification defines a way for clients to set a connection timeout and the affected API behavior is documented consistently.

Written by the indexing model from the issue text.