improved duration and minute selector (#2264)

* do not close modal if form is dirty
* deprecated TimesheetConfiguration
* inject timezone in form types
* cleanup usage of UserDateTimeFactory
* allow to configure increment steps for minutes
* use 15 minutes step for datetimepicker in project edit form
* use rounding rules for increments in minute select for begin and end
* allow duration in multi user and admin timesheet forms
* make dropdown values configurable

src/Form/TimesheetMultiUserEditForm.php

@@ -20,7 +20,6 @@ class TimesheetMultiUserEditForm extends TimesheetAdminEditForm
     {
         $options['allow_begin_datetime'] = true;
         $options['allow_end_datetime'] = true;
-        $options['allow_duration'] = false;
         $options['include_user'] = false;
 
         parent::buildForm($builder, $options);