message: Added note to README.md that resize is slow in debug mode. Also added some periods for consistency
diff: @@ -138,20 +138,20 @@ assert!(subimg.dimensions() == (100, 100));
  These are the functions defined in the `imageops` module. All functions operate on types that implement the `GenericImage` trait.
  + **blur**: Performs a Gaussian blur on the supplied image.
  -+ **brighten**: Brighten the supplied image
  -+ **huerotate**: Hue rotate the supplied image by degrees
  -+ **contrast**: Adjust the contrast of the supplied image
  -+ **crop**: Return a mutable view into an image
  ++ **brighten**: Brighten the supplied image.
  ++ **huerotate**: Hue rotate the supplied image by degrees.
  ++ **contrast**: Adjust the contrast of the supplied image.
  ++ **crop**: Return a mutable view into an image.
  + **filter3x3**: Perform a 3x3 box filter on the supplied image.
  -+ **flip_horizontal**: Flip an image horizontally
  -+ **flip_vertical**: Flip an image vertically
  -+ **grayscale**: Convert the supplied image to grayscale
  ++ **flip_horizontal**: Flip an image horizontally.
  ++ **flip_vertical**: Flip an image vertically.
  ++ **grayscale**: Convert the supplied image to grayscale.
  + **invert**: Invert each pixel within the supplied image This function operates in place.
  -+ **resize**: Resize the supplied image to the specified dimensions
  ++ **resize**: Resize the supplied image to the specified dimensions. Note that this is very slow in debug mode. Make sure to use release mode when using this.
  + **rotate180**: Rotate an image 180 degrees clockwise.
  + **rotate270**: Rotate an image 270 degrees clockwise.
  + **rotate90**: Rotate an image 90 degrees clockwise.
  -+ **unsharpen**: Performs an unsharpen mask on the supplied image
  ++ **unsharpen**: Performs an unsharpen mask on the supplied image.
  For more options, see the [`imageproc`](https://crates.io/crates/imageproc) crate.
  