Sync up keel chart with upstream

[rimusz]

Sync up keel chart changes with Helm upstream

[rusenask]

Do you think it would make sense to put Keel into a separate namespace? I can't remember what was historical reason for it to be in kube-system. With RBAC now it should work from anywhere.

[rimusz]

yup, we should use keel namespace

[rusenask]

I can do it in #137

[rimusz]

let me check the difference we have between charts and update it first here, then open PR upstream