Keepalived 2.0.10 + vlan handling mechanism

[n-Arno]

Following a rework of kube-keepalived-vip for a customer, we are contributing back the modifications.

Upgrade to Keepalived 2.0.10 ==> According to keepalived.org, versions 2.x are the go-to versions where bugfixes and improvements happens (no backport).

Custom interface handling ==> Ability to use an other interface rather than the internalIP/externalIP interface.

Vlan handling. ==> Ability to create vlan tagged interfaces complete with subnet mask and gateway route.

This is my first contribution back to an open-source projet, i hope i wrote here everything needed, in any case, 2 additional sections exist in the README (Custom interface and Advanced configuration) explaining what happens.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: arnoSCC To fully approve this pull request, please assign additional approvers. We suggest the following additional approver: bprashanth

If they are not already assigned, you can assign the PR to them by writing /assign @bprashanth in a comment when ready.

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Needs approval from an approver in each of these files: - **[hack/OWNERS](https://github.com/kubernetes/contrib/blob/master/hack/OWNERS)** - **[keepalived-vip/OWNERS](https://github.com/kubernetes/contrib/blob/master/keepalived-vip/OWNERS)** Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[n-Arno]

/assign @bprashanth

[n-Arno]

Ok, sorry i'm so bad at this. I'll manage to make hack/verify-all.sh works on my dev env and open a PR only when i'm sure the tests are ok.