1) Set document IDs to avoid duplicating documents;
2) Set the `creationTime` field of each document in the index;
3) set the `values`, `kinds` and `identifiers` fields for all documents;
4) Add a `Copy` method into the `Document` struct: this fixes the issue
where all the documents existing in the index point to the same Document
object;
5) Avoid using keystore redis;
6) Set imagePullPolicy to `Always` for crawler jobs.
Currently, the `kustomize` index in ElasticSearch is using dynamic
mapping, which sets the types of all the fields to `text`. However,
`text` field type is good for full-text value matching, and not good for
exact-value matching. For exact-value matching, the `keyword` filed
type should be used.
1) add the crawler binary and fix the crawler library
2) remove the readiness probe in the search backend
3) add config for redis keystore
4) add github_api_secret.txt file with instructions
