Update README.md

html2canvas changed links for their documentation

Author: drbeat

README.md

@@ -56,7 +56,7 @@ The `opt` parameter has the following optional fields:
 |filename    |string          |'file.pdf'                    |The default filename of the exported PDF.                                                                   |
 |image       |object          |{type: 'jpeg', quality: 0.95} |The image type and quality used to generate the PDF. See the Extra Features section below.                  |
 |enableLinks |boolean         |true                          |If enabled, PDF hyperlinks are automatically added ontop of all anchor tags.                                |
-|html2canvas |object          |{ }                           |Configuration options sent directly to `html2canvas` ([see here](https://html2canvas.hertzen.com/documentation.html#available-options) for usage).|
+|html2canvas |object          |{ }                           |Configuration options sent directly to `html2canvas` ([see here](https://html2canvas.hertzen.com/configuration) for usage).|
 |jsPDF       |object          |{ }                           |Configuration options sent directly to `jsPDF` ([see here](http://rawgit.com/MrRio/jsPDF/master/docs/jsPDF.html) for usage).|
 
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