LSQR algorithm with PyOpenCL

As part of the FreeCAD-Ship project I created a LSQR algorithm to solve Linear systems of equations, accelerated with OpenCL using PyOpenCL.

LSQR is a great, and relatively recent, iterative method to solve linear systems which can work with unsymmetrical rectangular matrix of an arbitrary range. Fortunately this method has also the property to fit so quite well to the GPU computing paradigm.

Bug fixes in FreeCAD-Ship

Several bugs have been fixed and already integrated in the master branch:

* Bad computed main frame coefficient.
* Crash in the tank volume computation when too low filling levels are required.
* Eventually bad computed floating area coefficient.
* Disabled the simulations framework (in development)

Since has been already integrated, I hope that in several days will be included in the Windows installers and in the Linux packages.