Update readme

Author: joppuyo

README.md

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 # ACF Image Aspect Ratio Crop Field
 
-Welcome to the Advanced Custom Fields Image Aspect Ratio Crop repository on Github.
+[![Build Status](https://travis-ci.org/joppuyo/acf-image-aspect-ratio-crop.svg?branch=master)](https://travis-ci.org/joppuyo/acf-image-aspect-ratio-crop)
 
-ACF field that allows user to crop image to a specific aspect ratio
+A field for Advanced Custom Field that forces the user to crop their image to specific aspect ratio after uploading. This is especially useful in responsive image use cases.
+
+After cropping, a new cropped image variant is created in the gallery and saved into the post. Thumbnails are also generated for the new image. User can re-crop the original image at any time from the post page.
+
+The cropped image variants are hidden by default in the media browser and on the media page but you can view then my selecting the "list view".
+
+## Cropping an image to 16:9 aspect ratio
+
+![Screenshot of cropping an image](assets/images/screenshot-1.png)
+
+## Option to re-crop the image after upload
+
+![Screenshot of the image field](assets/images/screenshot-2.png)
+
+## Thanks
+
+Special thanks to Anders Thorborg for [ACF Image Crop](https://github.com/andersthorborg/ACF-Image-Crop) which served as a inspiration for this plugin. Also, thanks to Fengyuan Chen for the [cropper.js](https://fengyuanchen.github.io/cropperjs/) library!
+
+## License
+
+GPL v2 or later