cca-operator create-instance command should support import of data

[OriHoch]

child of ViderumGlobal/PM#5

Add an optional attribute to CKAN instance configuration, e.g.:

importFrom:
  DB_URL: postgresql://.....
  SOLR_URL: http://foo.bar:8983
  .
  .

When create-instance command encounters this value:

• get the relevant DB / SOLR connection strings / minio storage URL
• either connect directly to the importFrom values, or schedule new infra. and import the data there
• deploy the helm chart - ensuring it uses the imported data

[OriHoch]

implemented in #27