Fix mapping for simple array types (i.e. string[])

When using a mapping of `string[]` in a namespaced class, it attempted to construct an object using `new \namespace\string ($value)` which is not valid.

I've also added a test case to test for this functionality.
Please add a docblock:
```
    /**
     * Convert a type name to a fully namespaced type name.
     *
     * @param string $type  Type name (simple type or class name)
     * @param string $strNs Base namespace that gets prepended to the type name
     *
     * @return string Fully-qualified type name with namespace
     */
```