Add README file for 'ckan_to_gn.py'

src/ckan2gn/README.md

@@ -0,0 +1,19 @@
+### NOTES for building & running 'ckan_to_gn.py' as a standalone docker image
+
+* Build
+```
+sudo docker build -t ckan2gn .
+```
+
+* Create .env file with 'CKAN2GN_CKAN_URL' 'CKAN2GN_GN_PASSWORD' 'CKAN2GN_GN_URL' 'CKAN2GN_GN_USERNAME' defined e.g.
+```
+CKAN2GN_CKAN_URL=https://myckan
+CKAN2GN_GN_PASSWORD=secretblah
+CKAN2GN_GN_URL=https://mygeonetwork
+CKAN2GN_GN_USERNAME=username
+```
+
+* Run
+```
+sudo docker run --env-file .env --network host ckan2gn
+```