Update README.md

Author: kean

README.md

@@ -43,7 +43,7 @@ DFImageManager is not just a loader, it's [a pipeline](#h_design) that loads ima
 - [WebP](https://developers.google.com/speed/webp/) support
 - Progressive image decoding (progressive JPEG and more)
 - Background image decompression and scaling in a single step
-- Scales large images (~6000x4000 px) and prepares them for display with ease
+- Scale large images (~6000x4000 px) and prepare them for display with ease
 - Resize and crop loaded images to [fit displayed size](https://developer.apple.com/library/ios/qa/qa1708/_index.html), add rounded corners or circle
 
 ##### Displaying