Add Edge to the Browser Support section (zenorocha#316)

Ref: zenorocha#267 (comment)

Author: alrra

readme.md

@@ -162,9 +162,9 @@ clipboard.destroy();
 
 This library relies on both [Selection](https://developer.mozilla.org/en-US/docs/Web/API/Selection) and [execCommand](https://developer.mozilla.org/en-US/docs/Web/API/Document/execCommand) APIs. The first one is [supported by all browsers](http://caniuse.com/#search=selection) while the second one is supported in the following browsers.
 
-| <img src="https://clipboardjs.com/assets/images/chrome.png" width="48px" height="48px" alt="Chrome logo"> | <img src="https://clipboardjs.com/assets/images/firefox.png" width="48px" height="48px" alt="Firefox logo"> | <img src="https://clipboardjs.com/assets/images/ie.png" width="48px" height="48px" alt="Internet Explorer logo"> | <img src="https://clipboardjs.com/assets/images/opera.png" width="48px" height="48px" alt="Opera logo"> | <img src="https://clipboardjs.com/assets/images/safari.png" width="48px" height="48px" alt="Safari logo"> |
-|:---:|:---:|:---:|:---:|:---:|
-| 42+ ✔ | 41+ ✔ | 9+ ✔ | 29+ ✔ | 10+ ✔ |
+ | <img src="http://clipboardjs.com/assets/images/chrome.png" width="48px" height="48px" alt="Chrome logo"> | <img src="http://clipboardjs.com/assets/images/edge.png" width="48px" height="48px" alt="Edge logo"> |  <img src="http://clipboardjs.com/assets/images/firefox.png" width="48px" height="48px" alt="Firefox logo"> | <img src="http://clipboardjs.com/assets/images/ie.png" width="48px" height="48px" alt="Internet Explorer logo"> | <img src="http://clipboardjs.com/assets/images/opera.png" width="48px" height="48px" alt="Opera logo"> | <img src="http://clipboardjs.com/assets/images/safari.png" width="48px" height="48px" alt="Safari logo"> |
+|:---:|:---:|:---:|:---:|:---:|:---:|
+| 42+ ✔ |  ✔ | 41+ ✔ | 9+ ✔ | 29+ ✔ | 10+ ✔ |
 
 The good news is that clipboard.js gracefully degrades if you need to support older browsers. All you have to do is show a tooltip saying `Copied!` when `success` event is called and `Press Ctrl+C to copy` when `error` event is called because the text is already selected.