[Story] Report generation

[andrewazores]

Reports should reside in a specific S3 bucket. If an existing report is found in the bucket then that report should either be downloaded temporarily by Cryostat and returned to the user as JSON/HTML through the API (old API compatibility), or returned to the client as a presigned GET request link directly through to S3 (new API for downloads). If no report is found in the S3 bucket then a new report should be generated, stored in S3, and a response sent to the client as before.

• [Task] Implement report generation with in-memory caching #59
• [Task] Store reports in S3 #60

[andrewazores]

Done.