Update README.md

Author: stephen99scott

README.md

@@ -8,3 +8,5 @@ The Data Store Rescope Tool (formerly known as the Data Store Push-Down Tool) id
 
 ## User Guide
 For installation and other information, please see the [User Guide](doc/DataStoreRescope_UserGuide.pdf).
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+This tool is also available for download on the [Matlab Central File Exchange](https://www.mathworks.com/matlabcentral/fileexchange/51160-data-store-rescope-tool).