Provide compile time and run time options for WebSocket URL and subprotocol fields
Removed capitals from a comment as requested, reinstated UDP test that was accidentally dropped and updated settings.js comment.
Add the datagram switch to the client as well as the server
Fixed test_sockets.py so that it uses temp directory correctly and cleans up automatically. Changed server port ranges to minimise chance of port collisions
Merge pull request #2020 from fadams/improve-websocket-config-options

Provide compile time and run time options for WebSocket URL and subproto...