updated instructions

README.md

@@ -42,6 +42,12 @@ or, to just change between versions after you've switched to using the gdcc repo
 
     update externaltool set toolurl=REPLACE(toolurl, 'v1.2', 'v1.3');
 
+## Fully Local Installation
+By default previewers reference several JavaScript libraries from their original web locations. If you would like to have a local installation that don't require access to other websites, you can use the localinstall.sh script. Download the repository to your local machine, change to the root directory where the localinstall.sh script is and run
+
+    ./localinstall.sh previewers/v1.4 https://<your host>/<your base path to the previewers>
+
+and the script will download all external JavaScript and css files required by the previewers for the version you specified and will update the example configuration commands in the 6.1curlcommands.md, 5.2curlcommands.md and pre5.2curlcommands.md files to reference your local URL. In the case above, using the parameters previewers/v1.4 and https://example.com/path would result example curl commands where the TextPreview.html would be available at https://example.com/path/previewers/v1.4/TextPreview.html.
 
 ## How do they work?