Include Deployed Images vulnreability mgmt. information in docs

[harisrini]

Vuln. mgmt section

Update the section to include information about Deployed Images/ Container vulnerability information.
Update information about vulnerability mapping and explain the column values for the table.

[jvillmer]

Documentation should detail that the tag column, at the time of export, reflects a historical value from the point of SHA creation - not a refreshed value(s) at the time when performing the export. This would mitigate the risk of users relying on this for realtime data in processes or analysis.