Add optional NVIDIA Management Library (NVML) Integration

NVML integration allows to automatically control GPUBoost from GROMACS
directly on supported GPUs. With this GROMACS either changes
application clocks automatically to the best performing setting or
informs the user that he should do it. The latter is done if permissions
do not allow to change application clocks.

Change-Id: I998e45596e2f556a5be7fa146fcd216ecae11452