Update README.md

Author: chrdavis

README.md

@@ -1,6 +1,6 @@
 Windows Shell extension to allow image types such as Portable Pixmap Format (PPM), Portable Graymap Format (PGM) and Portable Bitmap Format (PBM) to get thumbnail, properties and data object support in Windows Explorer.  Both ascii and binary versions of the above formats are supported. This extension will render thumbnails and properties (width, height, dimensions, bit depth) which will display in Windows Explorer.  It also implements a data handler extension which will permit copying the file from Explorer and pasting in applications such as MSPaint or Photoshop.  For more information about the file formats [click here](https://en.wikipedia.org/wiki/Netpbm_format).
 
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