Linalg 2 qr

updating qr calls 
Now qr most strongly fit matlab call syntax and also allows to get direct lapack results if needed
qr tests are split between complex/real inputs and no mre contain DISPLAY
i see the use for that. I think we should find a way to have

````
tie(_,r) = qr(a);
````

optimized could be interesting. Maybe having a check on the fact that child_c<0>(out) is colon_ is enough