Update CONTRIBUTING.md

Include Calesi setup steps in the contribution guide.

CONTRIBUTING.md

@@ -36,3 +36,26 @@ The following rule governs code contributions:
 * We use GitHub issues to track bugs and enhancement requests.
 
 * Please provide as much context as possible when you open an issue. The information you provide must be comprehensive enough to reproduce that issue for the assignee.
+
+## Development Setup
+
+As this is a CAP plugin, it is best to develop in the following calesi environment:
+```
+git clone --recursive https://github.com/cap-js/calesi.git for the calesi setup
+cd calesi
+npm i
+```
+Then clone this repository inside the calesi projects plugin folder:
+```
+cd plugins
+git clone https://github.com/cap-js/ORD
+cd ORD
+npm i
+```
+For testing an example app is available in the `xmpl` folder:
+```
+#If not already globally installed, install cds-dk
+npm install -g @sap/cds-dk
+cds w xmpl
+```
+After the CAP app has started, open this link in your browser: http://localhost:4004/open-resource-discovery/v1/documents/1