Add extraEnv and podLabels to helm chart deployment

[byxorna]

What is this?

Adds extraEnv and podLabels as top-level values in the helm chart. This is useful for environments that require specific labels to be added to pods to facilitate log/metrics collection.

Verification

I verified this renders properly by running the following, and verifying the labels and env vars are present and indented correctly.

kubernetes-reflector/src/helm/reflector $ helm template -f <(echo -e 'podLabels: { "foo":"bar" }\nextraEnv: [{name: "TEST", value: "example"}]') reflector ./

@sydorovdmytro

[winromulus]

LGTM