Cmake -- Possibility to configure, compile, install and package HOS-NWT with cmake

[Gjacquenot]

This branch adds the possibility to configure, compile, install and package HOS-NWT with cmake

Some modifications have been added to the code, so that it compiles with Gfortran 4.9.2 under MinGW 32 Bits

From cmake directory, it is possible to build the project with the following commands

mkdir -p build
cd build
cmake .. -G"Unix Generator" -DCMAKE_BUILD_TYPE=Release
make
make install

If a path to FFTW or Lapack library has to be given, one can call cmake with the following arguments
-DFFTW_ROOT=/path/to/fftw and -DLAPACK_ROOT=/path/to/lapack