az: add page (#2643)

* az: add page

pages/common/az.md

@@ -0,0 +1,27 @@
+# az
+
+> The official CLI tool for Microsoft Azure.
+
+- Log in to Azure:
+
+`az login`
+
+- Manage azure subscription information:
+
+`az account`
+
+- List all Azure Managed Disks:
+
+`az disk list`
+
+- List all Azure virtual machines:
+
+`az vm list`
+
+- Manage Azure Kubernetes Services:
+
+`az aks`
+
+- Manage Azure Network resources:
+
+`az network`