Fix failing tests on case-sensitive file systems.

src/Console/ShellDispatcher.php

@@ -201,7 +201,8 @@ class ShellDispatcher {
  * @return string|boolean Either the classname or false.
  */
 	protected function _shellExists($shell) {
-		$class = Inflector::camelize($shell);
+		$class = array_map('Cake\Utility\Inflector::camelize', explode('.', $shell));
+		$class = implode('.', $class);
 		$class = App::classname($class, 'Console/Command', 'Shell');
 		if (class_exists($class)) {
 			return $class;