Update readme to clarify how to install Elyra + Lab 2.x (elyra-ai#766)

Author: lresende

README.md

@@ -64,12 +64,19 @@ Elyra can be installed via PyPi:
 #### JupyterLab support
 
 * [JupyterLab](https://github.com/jupyterlab/jupyterlab) 1.x is supported on **Elyra 0.10.0 and below**
-* [JupyterLab](https://github.com/jupyterlab/jupyterlab) 2.x is supported on **Elyra 0.11.0-rc0 and above**
 
 via PyPi:
 ```bash
 pip install elyra && jupyter lab build
 ```
+
+* [JupyterLab](https://github.com/jupyterlab/jupyterlab) 2.x is supported on **Elyra 0.11.0-rc0 and above**
+
+via PyPi:
+```bash
+pip install --upgrade --pre elyra && jupyter lab build
+```
+
 Note: Ubuntu and CentOS users may need to use `pip3 install elyra` 
 
 ### Verify Installation