feat(deployment): allow add custom env values

[acamilleri]

Hello

Allow environment values to be passed to the operator container from a list of values defined by the env setting, and/or values from an object (configmap or secrets) with the envFrom setting.

I keep the compatibility of already defined env values with a range to transform the key value from a camelCase to snakeCase and transform it to uppercase.

          {{- range $key, $value := $.Values.env }}
            - name: {{ $key | snakecase | upper }}
              value: "{{ $value }}"
          {{- end }}