Update BOSH vSphere VM-VM Affinity Rules
Update BOSH vSphere VM-VM Affinity Rules

We update the docs with the newer nomenclature:

- `resource_pools` → `vm_extensions`
- `jobs` → `instance_groups`

The link that describes affinity was broken; the new link works.

We also use MySQL as an example instead of Hadoop; I don't know anyone
who has a BOSH-deployed Hadoop cluster.

cloudfoundry/docs-bosh