Tunneling connection protocol

Devices

• Handle ConversionError in RemoteValue, log a warning

Connection

• Raise if an initial connection can not be established, auto-reconnect only when the connection was successful once
• Add support for TCP tunnel connections
• Optionally run KNXIPInterface in separate thread
• Handle separate Tunneling control and data endpoints
• Fix rate limiter wait time: don't add time waiting for ACK or L_DATA.con frames to the rate_limit

Internals

• Some refactoring and code movement in the io module - especially in KNXIPInterface; renamed UDPClient to UDPTransport
• Cleanup some list generating code in the knxip module