Function Mocker now compatible with PHPUnit 6

A quick announcement for a quick update.

PHPUnit adopted namespaces

PhpUnit is now on version 6.1 and has dropped its Namespace_Less_Class_Naming_System in favor of a modern one like PHPUnit\Framework\SomeClass.
That’s not nearly all of it, but the change breeaks compatibility with the function-mocker library.
Having just updated it to support Patchwork new features, I did not want to let Function Mocker limping its way into the new PHPUnit version.
Prompted by an issue on the repository I’ve updated function-mocker to support PHPUnit version ~5.0 and ~6.0 to leave no one behind.

See function-mocker repository for more information.