GMP builds using Microsoft C/C++ or Intel C++ Compilers with MSYS2

[sav_ix at ukr.net]

    Hi, everyone, 


For those who are interested, there is a short manual concerning GMP builds using Microsoft C/C++ or Intel C++ Compilers with MSYS2, as a part of more general report (https://sympa.inria.fr/sympa/arc/mpfr/2016-02/msg00000.html ). 

An offered patch for GMP sources has minor flaws, thus proposals with improvements are welcome. 



Regards, 

Alexander