Added support for array-style callable to FunctionCallDefinitionDumper.

[jmalloc]

I had a definition failure occur with the following code:

$container->call([$object, 'injectDependencies']);

And the dumper failed with the error message:

ReflectionFunction::__construct() expects parameter 1 to be string, array given

This PR adds explicit report for array callables to the dumper.

[mnapoli]

Thank you for this quick fix! I have merged manually and fixed the short array in the tests so that it runs on PHP 5.3 too.

I have just released v4.2.2 (https://github.com/mnapoli/PHP-DI/releases/tag/4.2.2) :)