Merge branch '2.8' into 3.0

* 2.8:
  fixed typo
  fixed typo
  Fixed a minor XML issue in a translation file
  Fix merge
  Fix merge
  Fix merge
  Fix merge
  Update twig.html.twig
  PhpUnitNoDedicateAssertFixer results
  Improve Norwegian translations
  [2.7] [FrameworkBundle] minor fix tests added by #17569
  Fixed the antialiasing of the toolbar text
  Simplify markdown for PR template
  fixed CS
  fixed CS
  documented the $url parameter better
  [Form] add test for ArrayChoiceList handling null
  [Form] fix edge cases with choice placeholder
  register commands from kernel when accessing list
  Update FileSystem

Author: fabpot

Tests/InlineTest.php

@@ -318,7 +318,7 @@ public function getTestsForParseWithMapObjects()
             array("'#cfcfcf'", '#cfcfcf'),
             array('::form_base.html.twig', '::form_base.html.twig'),
 
-            array('2007-10-30', mktime(0, 0, 0, 10, 30, 2007)),
+            array('2007-10-30', gmmktime(0, 0, 0, 10, 30, 2007)),
             array('2007-10-30T02:59:43Z', gmmktime(2, 59, 43, 10, 30, 2007)),
             array('2007-10-30 02:59:43 Z', gmmktime(2, 59, 43, 10, 30, 2007)),
             array('1960-10-30 02:59:43 Z', gmmktime(2, 59, 43, 10, 30, 1960)),