Modification: new data model for history, more compact, more efficient. A
summary table is used as cache for history stats display.
New: a Perl script fill_history.pl was added to simulate a high load on
history table (making the efficiency of the new data model obvious).
Modification: function prepend_append_array_items moved from
include/functions_search.inc.php to include/functions_search.inc.php since
this function is used in new file admin/history.php
Modification: admin/images/*_stats.img.php replaced by a simpler and more
generic admin/images/stats.img.php unique file.
New: a history detail search page was added. Currently, only start and end
dates can be modified, it's just a beginning.