feat: Allow specifying deployment annotations

[tomi-bigpi]

Currently the chart does not allow setting additional annotations for the deployment itself. This is required, for example, when using https://github.com/stakater/Reloader to automatically restart the deployment when AWS rotates secrets.

An example of the required tags from Reloader:

kind: Deployment
metadata:
  name: foo
  annotations:
    reloader.stakater.com/auto: "true"
spec:
  template:
    metadata: