Merge pull request #559 from stloyd/patch-2

[TarDownloader] Force overwrite if previous extract failed and was not r...

src/Composer/Downloader/TarDownloader.php

@@ -28,6 +28,6 @@ class TarDownloader extends ArchiveDownloader
     {
         // Can throw an UnexpectedValueException
         $archive = new \PharData($file);
-        $archive->extractTo($path);
+        $archive->extractTo($path, null, true);
     }
 }