Update README.md Quickstart instructions to start a notebooks from the...

Update README.md Quickstart instructions to start a notebooks from the JupyterLab kernel made for spack installed software

README.md

 # ebrains-spack-builds
 
-Build and distribute software with Spack
+Build and distribute software tools with Spack for the EBRAINS Collaboratory Lab containers.  
 
-**Quickstart**
+**Quickstart for Notebooks**  
+- Open a terminal at a running Collaboratory Lab Container and execute the following:
+```
+#update modulepath of JupterLab container to include spack arch modulefiles path
+export MODULEPATH=$MODULEPATH:/srv/test-build/spack/share/spack/modules/linux-centos7-broadwell/
+
+#start JupyterLab kernel made for spack
+jupyter kernelspec install --user /srv/test-build/ebrains-spack-builds/spack_python_kernel_release_20210930/
+```
+- Then select File > New Launcher
+- Open a new Notebook with the "EBRAINS_release_20210930" kernel
+- Import the tools available with spack:
+```
+import nest
+import arbor
+import neuron
+```
+
+**Quickstart for terminal**  
 - Open a terminal at a running Collaboratory Lab Container and execute the following:
 ```
  git clone https://gitlab.ebrains.eu/akarmas/ebrains-spack-builds.git