Update the guidance for the bosh-setup template v3.0.0

[bingosummer]

No need to run unit tests since the changes are only about documents.

Changelog

• The following docs are updated for the new bosh-setup template
  • application-gateway
  • configure-resource-groups/separate-vm-in-a-different-resource-group.md
  • configure-resource-groups/separate-network-in-a-different-resource-group.md
  • deploy-cloudfoundry-with-availability-sets
  • deploy-multiple-network-interfaces
  • push-your-first-net-application-to-cloud-foundry-on-azure
  • cf-ssh-application

[cfdreddbot]

Hey bingosummer!

Thanks for submitting this pull request! I'm here to inform the recipients of the pull request that you and the commit authors have already signed the CLA.