Make Project Management asset task editor default start date of task

to start date of project.

docs/changelog/7.x.x.txt

@@ -7,7 +7,7 @@
  - Fixed some bugs in the SQLForm. Also refactored parts of the SQLForm to
    reduce the number of database queries and lessen the amount of data being
    uploaded when images are put in the form. (Martin Kamerbeek / Procolix)
-
+ - change: PM asset task editor now defaults start date to start of project
 
 7.0.8
  - Fixed a couple of minor bugs with the default values of the Request

lib/WebGUI/Asset/Wobject/ProjectManager.pm

@@ -843,8 +843,8 @@ sub www_editTask {
 				});				
    #Set some hidden variables to make it easy to reset data in javascript
    my $duration = $task->{duration};
-   my $start = $dt->epochToSet($task->{startDate});
-   my $end = $dt->epochToSet($task->{endDate});
+   my $start = $dt->epochToSet($db->quickArray('SELECT startDate, startDate FROM PM_task WHERE projectId = ? ORDER BY sequenceNumber LIMIT 1', [$projectId]));
+   my $end = $start;
    my $dependant = $task->{dependants};
    														   
    $var->{'form.header'} .= WebGUI::Form::hidden($session, {