Use a dedicated VM/EC2 instance for file server in Windows templates

In the original design, Windows templates used a dedicated VM (EC2 instance) for file servers. Then, the file servers were moved to the primary VM. The reasons for that change were:

1. The strategic goal was to move away from using file shares and use managed cloud storages instead.
2. A dedicated VM for file server increases the infrastructure cost, but does not increase the system availability (the system is down if either VM is down).
3. A dedicated VM requires additional effort for creating and managing images of the file server VMs.

Now there are new reasons to come back to the original design:

1. #287 (Support for sharing file servers across multiple deployments).
2. #289

Other advantages of using a dedicated VM for file server:

- Ability to use an I/O optimized VM type for file server.
- Symmetric utilization of primary and node/standby VMs.
- Ability to configure an independent backup plan for file server VMs.

> Supporting both design options would significantly increase complexity of the templates.

All the Windows templates for AWS and Azure should be changed to use a dedicated VM/EC2 instances for file servers.

Requirements:

- File server must not be co-located with the primary VM.
- The file servers VMs should be launched from the base OS images (no pre-baked images).
- The templates should support setting VM types, disk sizes, and I/O properties (disk type / IOPS / throughput) of the file server VMs.
- The templates should support cross-deployment sharing of file servers ( #287)