fixed link and text in contributing

Author: BartMassey

CONTRIBUTING.md

@@ -42,4 +42,6 @@ You'll need a [GitHub account](https://github.com/join)!
 
 Sometimes, a maintainer of an awesome list will ask you to edit your Pull Request before it is included. This is normally due to spelling errors or because your PR didn't match the awesome-* list guidelines.
 
-[Here](https://github.com/RichardLitt/knowledge/blob/master/github/amending-a-commit-guide.md) is a write up on how to change a Pull Request, and the different ways you can do that.
+[This commit-change guide](https://github.com/RichardLitt/knowledge/blob/master/github/amending-a-commit-guide.md)
+is a writeup on the several ways you can update a Pull
+Request.