Misleading warning on rerun
When doing `mdrun -rerun` with multiple energy groups the following warning is issued:
Multiple energy groups is not implemented for GPUs, falling back to the CPU. For better performance, run on the GPU without energy groups and then do gmx mdrun -rerun option on the trajectory with an energy group .tpr file.
However, this is already a rerun i.e. this warning ask one to do what the user is already doing. This is misleading, especially for inexperienced users. This warning should not be issued when `-rerun` flag is used.