Add Azure Resource Manager templates to contrib folder

contrib/azurerm/README.md

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+# Kubernetes on Azure with Azure Resource Group Templates
+
+Provision the base infrastructure for a Kubernetes cluster by using [Azure Resource Group Templates](https://docs.microsoft.com/en-us/azure/azure-resource-manager/resource-group-authoring-templates)
+
+## Status
+
+This will provision the base infrastructure (vnet, vms, nics, ips, ...) needed for Kubernetes in Azure into the specified
+Resource Group. It will not install Kubernetes itself, this has to be done in a later step by yourself (using kargo of course).
+
+## Requirements
+
+- [Install azure-cli](https://docs.microsoft.com/en-us/azure/xplat-cli-install)
+- [Login with azure-cli](https://docs.microsoft.com/en-us/azure/xplat-cli-connect)
+- Dedicated Resource Group created in the Azure Portal or through azure-cli
+
+## Configuration through group_vars/all
+
+You have to modify at least one variable in group_vars/all, which is the **cluster_name** variable. It must be globally
+unique due to some restrictions in Azure. Most other variables should be self explanatory if you have some basic Kubernetes
+experience.
+
+## Bastion host
+
+You can enable the use of a Bastion Host by changing **use_bastion** in group_vars/all to **true**. The generated
+templates will then include an additional bastion VM which can then be used to connect to the masters and nodes. The option
+also removes all public IPs from all other VMs. 
+
+## Generating and applying
+
+To generate and apply the templates, call:
+
+```shell
+$ ./apply-rg.sh <resource_group_name>
+```
+
+If you change something in the configuration (e.g. number of nodes) later, you can call this again and Azure will
+take care about creating/modifying whatever is needed.
+
+## Clearing a resource group
+
+If you need to delete all resources from a resource group, simply call:
+
+```shell
+$ ./clear-rg.sh <resource_group_name>
+```
+
+**WARNING** this really deletes everything from your resource group, including everything that was later created by you!
+
+
+## Generating an inventory for kargo
+
+After you have applied the templates, you can generate an inventory with this call:
+
+```shell
+$ ./generate-inventory.sh <resource_group_name>
+```
+
+It will create the file ./inventory which can then be used with kargo, e.g.:
+
+```shell
+$ cd kargo-root-dir
+$ ansible-playbook -i contrib/azurerm/inventory -u devops --become -e "@inventory/group_vars/all.yml" cluster.yml
+```
+