Delimiter flags for values

Sometimes we need to include strings in values that will be templated by helm itself (via tpl function). In this case we can change helmwave delimiters so it won't render foreign expressions.

cat values.yml

## Prometheus Exporter / Metrics
##
metrics:
  service:
    annotations:
      service_name: [[.Release.Store.metadata | quote]]
      prometheus.io/scrape: "true"
      prometheus.io/port: "{{ .Values.metrics.service.port }}"

cat helmwave.yml

version: 0.25.0

repositories:
  - name: bitnami
    url: https://charts.bitnami.com/bitnami

.options: &options
  namespace: my-namespace
  wait: true

releases:
  - name: nginx
    <<: *options
    chart: bitnami/nginx
    store:
      metadata: 123
    values:
      - src: values.yml
        delimiter_left: "[["
        delimiter_right: "]]"