Ansible multi nic templates broke the nicX relation to network order in network_data.yaml

With the Heat multi-nic example templates the loop.index was used to set the nicX.
With Heat the iteration was on all networks in 'network_data.yaml', so you would end up with:

Given network data:
 - name: External
 - name: InternalApi
 - name: Storage
 - name: StorageMgmt
 - name: Tenant

For a Controller with networks ctlplane, External, InternalApi, Storage, StorageMgmt, Tenant the nicX in the generated template would be:

    ctlplane: nic1
    External: nic2
    InternalApi: nic3
    Storage: nic4
    StorageMgmt: nic5
    Tenant: nic6

For a compute with networks ctlplane, external_bridge, InternalApi, Storage, Tenant the nicX in the generated template would be:

   ctlplane: nic1
   external_bridge: nic2
   InternalApi: nic3
   Storage: nic4
   Tenant: nic6

With the ansible templates the j2 is iterating over role networks only _and_ the External network is always put last in the DVR multi_nic templates. So we end up with:

For Controllers:
    ctlplane: nic1
    InternalApi: nic2
    Storage: nic3
    StorageMgmt: nic4
    Tenant: nic5
    External: nic6

For Compute:
   ctlplane: nic1
   InternalApi: nic2
   Storage: nic3
   Tenant: nic4
   external_bridge: nic5

The result is that anyone using environments/net-multiple-nics.yaml out of the box will have to re-wire the physical cabling in the datacenter.

The same is true for users of environments/net-multiple-nics-vlans.yaml