[WIP] Call functions with constref params (please do not merge yet)

added a **failing** test for the scenario where the client function has const ref pointers and is not consuming the input immediately but rather storing for later reuse. 

Note: if the function is using the input while its being invoked, its working ok - meaning cpgf is using a temporary variable, that goes out of scope when the pointer is used later.

Also, if the const ref is removed and only the pointer part is left - its working ok too.

Ideally, this scenario should work exactly the same as without const refs.

Real life issue affected by this: svalaskevicius/qtjs-generator#23