Added keyboard support information

README.md

@@ -6,6 +6,26 @@
 
 
 
+## Keyboard support
+
+- `Esc`: Cancel the cropping.
+- `Enter`: Complete the cropping.
+- `Delete`: Delete the uploaded or cropped image.
+- `←`: Move the image to left by 1 pixel.
+- `→`: Move the image to right by 1 pixel.
+- `↑`: Move the image to top by 1 pixel.
+- `↓`: Move the image to bottom by 1 pixel.
+- `M`: Enable to move the image by dragging.
+- `C`: Enable to crop on the image by dragging.
+- `I`: Zoom in the image.
+- `O`: Zoom out the image.
+- `L`: Rotate the image to the left.
+- `R`: Rotate the image to the right.
+- `H`: Flip the image on the horizontal.
+- `V`: Flip the image on the vertical.
+
+
+
 ## Browser support
 
 - Chrome (latest 2)