Ingress shouldn't be created for apps with empty Vhost

[retpolanne]

If you toggle Ingress on a Teresa server deployment after some apps have been created without it, ingresses might be created without any host.

To replicate this bug:

• Change the teresa.io/app annotation – leave an empty string on virtualHost and false on reserveStaticIp
• Make sure ingress is enabled on Teresa
• Make a web deployment
• Ingress will be created, without any Host

  spec:
    rules:
    - http:
        paths:
        - backend:
            serviceName: myapp
            servicePort: 80
          path: /

Alternatively, the path can be a catch all /*, this way it'll work the same way as specify no rules.