Update krew install doc (#42)

* Update krew install doc

Co-authored-by: Andrei Kvapil <[email protected]>

Author: astraw99

README.md

@@ -9,6 +9,13 @@ Start a root shell in the node's host OS running. Uses an alpine pod with nsente
 
 using [krew](https://krew.sigs.k8s.io/):
 
+Plugin can be installed from the official krew repository:
+
+<pre>
+kubectl krew install node-shell
+</pre>
+
+Or from our own krew repository:
 <pre>
 kubectl krew index add kvaps <a href="https://github.com/kvaps/krew-index">https://github.com/kvaps/krew-index</a>
 kubectl krew install kvaps/node-shell