Fix crashes if viewback functions are called before the server is started. Fix warnings at higher warning levels. Move the command callback next to the debug output callback to avoid the extra function call. Add documentation. Other stuff too.
Allow the game to specify a range for a variable, and the client should stick to rendering it using that range.
Allow the client to keep track of whether a data channel is visible.
I think this is a slightly better assumption, and it doesn't assert when you kill the server while the client is still running.
Add the ability to use groups to organize many streams of data. Rename "registrations" to "channels" as "registrations" now refers to the entire data package describing the channels, groups, and labels. Changed the field numbers in the protobuf but it's okay because there are no clients in the wild. Changed the interface a little bit for clarity. Change // comments to /* */ comments.