message: Make rayon an optional dependency
diff: @@ -37,6 +37,7 @@ optional = true
  [dependencies.jpeg-decoder]
  version = "0.1"
  +default-features = false
  optional = true
  [dependencies.png]
  @@ -52,7 +53,7 @@ num-complex = "0.1.32"
  glob = "0.2.10"
  [features]
  -default = ["gif_codec", "jpeg", "ico", "png_codec", "pnm", "ppm", "tga", "tiff", "webp", "bmp", "hdr"]
  +default = ["gif_codec", "jpeg", "ico", "png_codec", "pnm", "ppm", "tga", "tiff", "webp", "bmp", "hdr", "jpeg_rayon"]
  gif_codec = ["gif"]
  ico = ["bmp", "png_codec"]
  @@ -65,5 +66,6 @@ tiff = []
  webp = []
  bmp = []
  hdr = ["scoped_threadpool"]
  +jpeg_rayon = ["jpeg-decoder/rayon"]
  benchmarks = []
  