Allow rejection of incoming connections

[Kittyfisto]

It shall be possible to hook into the process of processing an incoming connection and rejecting it.
Example usage:

• Only allow incoming connections from certain ip-addresses
• Only allow incoming connections at certain times of day (this allows us to send a 'busy' response to the client instead of the client timing out)

This shall be done by implementing a new interface which offers a single callback method:

public interface IConnectionInspector
{
    [Pure]
    bool AllowIncomingConnection(EndPoint remoteEndPoint);
}