|SOURCE|
[Common::GameStateManager]
* Added member functions to show and hide the overlay or each element of the
  overlay
* Moved the overlay rendering from always rendering in Execute to rendering if
  requested by the user
* Overlays include (for now) the following:
  Frames Per Second - The total frame count over the last second
  Frame Time - Time taken to render a frame
  Elapsed Time - Time since program start
  .beat Time - Swatch .beat time
  Build Information - Useful information when debugging the game
[Common::Game]
* All overlays are displayed by default