Improve layout of revision-history for multi-row CustomGroups

When viewing the revision history for multi-row CustomGroups, one must navigate to the changelog tab, guess at which revisions involve the custom record, and then pay careful attention to the id#'s (which may not be aligned well). This should be improved.

Example: in the "Career" tab, show a link to "View revisions". The link shows a popup with the logging report filtered to only include changes to the "Career" data. (This should be repeated in each of the custom-data-based extensions – hrcareer, hrident, hrmed, hrqual, hrvisa.)