Renplay 2.9.0

Added

• Unity WebGL games and Godot web builds install and play, like HTML games: in a sandboxed frame,
  with their saves on the server. Tested with NaughtyPhone (Unity 6) and Diggz for Vex (Godot 4.7).
  On itch.io these are the versions that play in the browser.
• Games of engines other than Ren'Py are marked Beta in the library, on their page and in Add
  games: they work, with fewer features.
• Games that keep their saves in IndexedDB (Unity, Godot, RPG Maker MZ, and others) keep them on the
  server: the sandboxed frame gets an in-memory IndexedDB that is restored before the game starts
  and stored after every write.

Changed

• Godot PC downloads say to use the game's web build instead.