Add slurm batch scripts

[jchodera]

We should add LSF and slurm batch scripts to examples.

[jchodera]

Here's a rudimentary example modified from one of @Lnaden's scripts, though this one seems to depend on MPS:

#!/bin/bash
#BSUB -W 24:00
#BSUB -o abl-imatinib-explicit.%J.log
#BSUB -env "all, LSB_START_JOB_MPS=Y"
#BSUB -n 4 -R "rusage[ngpus_excl_p=1,mem=8]"
#BSUB -m ls-gpu
#BSUB -J "abl-imatinib-explicit"

# Run the simulation with verbose output:
#source activate yank16
export PREFIX="explicit"
build_mpirun_configfile  "yank script --yaml=$PREFIX.yaml"
mpiexec.hydra -f hostfile -configfile configfile

[jchodera]

I think the LSF part is done now and the slurm part is left.