implement per-service annotations to control IP advertisment

[asteven]

Fixes #75.

Please let me know if I did something obviously wrong or if there are better/nicer ways to code this.
This is the first go code I ever wrote, I'm a Python programmer at heart.

[murali-reddy]

thanks for the PR @asteven Nice job for first go code :)

Service type in the annotations

• kube-router.io/service.advertise.cluster
• kube-router.io/service.advertise.external
• kube-router.io/service.advertise.loadbalancer

does not sound complete. Can we make it to

• kube-router.io/service.advertise.clusterip
• kube-router.io/service.advertise.externalip
• kube-router.io/service.advertise.loadbalancerip

[asteven]

thanks for the PR @asteven Nice job for first go code :)

Thanks ;-)

Service type in the annotations

* `kube-router.io/service.advertise.cluster`

* `kube-router.io/service.advertise.external`

* `kube-router.io/service.advertise.loadbalancer`

does not sound complete. Can we make it to

* `kube-router.io/service.advertise.clusterip`

* `kube-router.io/service.advertise.externalip`

* `kube-router.io/service.advertise.loadbalancerip`

Done.

[murali-reddy]

Thanks @asteven