anchor: love.graphics.getCanvasFormats
  Gets the available Canvas formats, and whether each is supported.
  formats = love.graphics.getCanvasFormats()
  formats table A table containing CanvasFormats as keys, and a boolean indicating whether the format is supported as values. Not all systems support all formats.
  formats = love.graphics.getCanvasFormats( readable )
  readable boolean If true, the returned formats will only be indicated as supported if readable flag set to true for that format, and vice versa if the parameter is false.
  formats table A table containing CanvasFormats as keys, and a boolean indicating whether the format is supported as values (taking into account the readable parameter). Not all systems support all formats.