Add Examples

[edgardevo]

As a Data Engineer, I would like to see code examples of usage and setup. The following setups:

1. Use Dataform2Looker as a step for a Dataform git repository. The Challenge here is the limitation that BigQuery is used as the backend for the metadata of the columns. Think of a scheduled CI/CD job to create a PR to a Looker project only if there are changes in the repository after X amount of days
2. Use Dataform2Looker as a step for a Looker Repository. The challenge is the workflow should pull the latest information from a Dataform repository, Generate the Dataform compilation, and use it as input for df2looker, once the Metadata is generated the PR should be created ONLY if there are changes in the data, this means there should be a diff check between existing Looker Views and the generated Views from Repo. Careful with error handling in case the BigQuery table doesn't exist yet