Extend cheatsheat doc

doc/cheatsheet.md

@@ -7,5 +7,12 @@ List of popular commands and shortcuts
 !^ - first argument
 !$ - last argument
 !* - all arguments
-```
 
+# Kubernetes
+# ~/.kube/config
+kubectl config get-contexts
+kubectl config use-context <context>
+
+# AWS
+aws eks update-kubeconfig --name nas
+```