Some methods act the same on both sides, and so can be in utility
classes. Others are only needed on one side, and so do not really need
to be part of the proxy.
- Remove TurtleVisionCamera. It would be possible to add this back in
the future, but for now it is unused and so should be removed.
- Move frame info (cursor blink, current render frame) into a
FrameInfo class.
- Move record methods (name, playing a record) into a RecordUtil class.
- The current page is always centred when rendering in a GUI, with
the turned pages moving from the sides.
- Pages are no longer evenly distributed from the centre - they follow
an exponential decay curve, so ones further out are closer together
(a bit like an open book).
- Render pages and books in item frames/in-hand (rather than just
single pages).
This currently does some very dirty things with z values in order to
prevent z-fighting. It would be nice to avoid that, though turning off
writing to the z buffer causes issues with the bounding box.
