Precise specification of all three REST API endpoints to retrieve rule hits by Insights Operator

[tisnik]

Three new endpoints will be needed:

1. Check status of given x-rh-insights-request-id (let it be processed/unknown for this moment - but I can imagine it will be done in a much better way later)
2. List of all rule hits (all identified by x-rh-insights-request-id) for given cluster (the list should also contain timestamp)
3. Retrieve simplified results (see below) for given x-rh-insights-request-id

Please note that we’ll still be processing Bearer token, org_id/account_number etc. as usual, so we’ll be able to say “hey, this cluster does not belong to your company, go away”.