Documentation includes keyboard shortcuts.

README.md

@@ -19,12 +19,15 @@ include it anywhere in your HTML.
 
 ## Features
 * **Easily Stylable:** [These are the default styles](https://github.com/brianblakely/nodep-date-input-polyfill/blob/master/nodep-date-input-polyfill.scss),
-which you may overwrite with your own.
+which you may override with your own.
 
 * **Polyfills `valueAsDate` and `valueAsNumber`:**
 [Learn more about these properties.](https://developer.mozilla.org/en-US/docs/Web/API/HTMLInputElement#property-valueasdate)
 They behave as getters and setters.
 
+* **Keyboard Shortcuts:** `Esc` will hide the datepicker. `Up/Down` will
+decrement/increment the date by one day.
+
 ## Contributing
 
 ### Local Development