(legacy) fix crashreport "PHP Warning:  array_keys() expects parameter 1 to be array, null given in /usr/local/www/diag_logs_filter_summary.php on line 140"

Slight refactoring in the general area while at it...

This patch fixes a few different issues.
- Prevent the user from selecting all rules at once, the browser probably can't render that amount of data resulting in sloppy behaviour.
- When querying the alerts, show an overlay during the process. This might take some time, depending on the amount of logged items
- Change number of rows selection to more sane defaults.
- Refresh data after "apply selection", to return to the right page

(ui) add refresh method to jquery.bootgrid.js, temporary added this into the compiled js file should extension should probably move to somewhere else.