Initial migration to new socks-rtc and rtc-net

 * Updated package to use this version of uproxy-networking: https://github.com/uProxy/uproxy-networking/pull/119 also to avoid using the broken 11.0.1 version of uproxy-lib
 * renamed uproxy.json to be freedom-module.json (to fit standard style for freedom-modules)
 * Removed global socks-to-rtc and rtc-to-net modules & replaced then with remote-instance-specific instances of the socks-to-rtc and rtc-to-net classes that are constructed as/when they are needed. This removes the need to any peer-information to be in the signalling messages (PeerSignal should now just be a WebRtc Signal Message)  
 * Added instance-level configuration for socks-to-rtc and rtc-to-net.
 * Added closing of the rtc-to-net module when the access is revoked. 
 * Added notification for when rtc-to-net closes. 

Still to do: 
 * use dynamic port (https://github.com/uProxy/uproxy/issues/367)
To me, `remoteProxyServerInstance` seems verbose, especially given the type information that it's already a `Core.RemoteInstance`.