minor #77 updated deprecated use of Yaml::parse (sgilberg)

This PR was merged into the 2.1.x-dev branch.

Discussion
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updated deprecated use of Yaml::parse

Per [Symfony documentation] (http://symfony.com/doc/current/components/yaml/introduction.html): "Passing a filename is deprecated in Symfony 2.2, and will be removed in Symfony 3.0."

Updated use:
`Yaml::parse(file_get_contents('/path/to/file.yml'));`

Commits
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5bff259 updated deprecated use of Yaml::parse

Tests/ProcessorTest.php

@@ -102,7 +102,7 @@ public function testParameterHandling($testCaseName)
                 'environment' => array(),
                 'interactive' => false,
             ),
-            (array) Yaml::parse($dataDir.'/setup.yml')
+            (array) Yaml::parse(file_get_contents($dataDir.'/setup.yml'))
         );
 
         $workingDir = sys_get_temp_dir() . '/incenteev_parameter_handler';