Add hook to alter journal table output by other modules

Regarding Demo module integration, it would be great, if Demo module was able to add f.e. a column containing reset links for snapshots. Although something similar has been discussed on the devel list as a valuable core feature for D7, it should be possible to implement a

hook_journal_table(array &$header, array &$rows, array &$data);

or similar in the meanwhile. Other modules will need to have access to

- the table header definition
- raw data of a row (an object fetched from a database result resource) as well as
- a structured and pre-rendered data array of a row for hook_table()

Since we deal with log entries, only table rows are affected.