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

tests/Saml/Logout/SamlLogoutHandlerTest.php

@@ -44,7 +44,7 @@ class SamlLogoutHandlerTest extends TestCase
         $auth->expects($this->once())->method('getSLOurl')->willReturn('/logout');
         $auth->expects($this->once())->method('logout')->willReturnCallback(function () {
             $args = \func_get_args();
-            self::assertEquals(null, $args[0]);
+            self::assertNull($args[0]);
             self::assertEquals([], $args[1]);
             self::assertEquals('tony', $args[2]);
             self::assertEquals('foo-bar', $args[3]);