Server now can handle multiple API versions simultaneously as described in RFC. The current version is '2'. Added new file API_VERSIONS.md with version history and brief description of FreeFeed versioning principles for API users.
Internally, the requested API version is available via the ctx.state.apiVersion property in REST controllers and via the socket.apiVersion property in the realtime handler.
Added new realtime command, 'status'. It returns the current properties of socket connection, which includes userId, apiVersion and rooms fields.
ctx.state.apiVersionproperty in REST controllers and via thesocket.apiVersionproperty in the realtime handler.