Add $parameter option given to 'call_user_func'

It could be great to have the possibility to send parameter in 'call_user_func(..,$parameter)'

Thanks.
request: Add $parameter option given to 'call_user_func'
-fix indentation
-parameter renamed in parameters
-call_user_func_array is used instead of call_user_func
-default value for parameters is defined (array())
-some tests and documentation added
In Tests/Admin/BaseFieldDescriptionTest.php:
Use the original count of method('getFoo')

> @@ -90,9 +90,38 @@ public function testGetValue()
>          $description->setOption('code', 'getFoo');
>  
>          $mock = $this->getMock('stdClass', array('getFoo'));
> -        $mock->expects($this->once())->method('getFoo')->will($this->returnValue(42));
> +        $mock->expects($this->any())->method('getFoo')->will($this->returnValue(42));
Merge pull request #1414 from bricelalu/patch-1

Add $parameter option given to 'call_user_func'