merged branch jdewit/master (PR #2242)

Commits
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6d8c4a8 change nested collection indentation from 2 to 4

Discussion
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Changed Yaml Dumper nested collection indentation

This PR changes the dumpers nested collection indentation from 2 to 4 which seems to be the standard.

src/Symfony/Component/Yaml/Dumper.php

@@ -44,7 +44,7 @@ class Dumper
                     $prefix,
                     $isAHash ? Inline::dump($key).':' : '-',
                     $willBeInlined ? ' ' : "\n",
-                    $this->dump($value, $inline - 1, $willBeInlined ? 0 : $indent + 2)
+                    $this->dump($value, $inline - 1, $willBeInlined ? 0 : $indent + 4)
                 ).($willBeInlined ? "\n" : '');
             }
         }