Better event handling and more specific event definition

[shimondoodkin]

After investigating some Addon potential I found that the behaviour of the events differs between the different pages. More specifically, in order to get the icon next to the header for itemReport.php (like with the Tree View) you set an event in the addon such that

{{{
$event[_GTD_ON_DATA]['itemReport'] = "myaddon.inc.php";
}}}

This, however, does not work for summary.php, listItems.php, or weekly.php. In fact, the gtd_handleEvent(_GTD_ON_DATA,$pagename); call doesn't take place in the same location on those pages, and the addons don't even seem to have been parsed prior to this call either.

Should the pages behave consistently for the _GTD_ON_DATA call, or should there be an additional event such as _GTD_AFTER_TITLE that could be used in its place?