Slurm-pipeline

Added `--compressLevel` and `--randomSleep` options to `sbatch.py`.

Added compression of input files to `sbatch.py` and an `--uncompress`
option to turn this off. Thanks to
[holtgrewe](https://github.com/holtgrewe) for this suggestion.

Updated `.travis.yml` and build status image URL on `README.md`.

Added conda install instructions to `README.md`.

Improved `README.md` description of `sbatch.py`.

Added JSON output of all SLURM job numbers and added to `README.md` to
describe how to easily use the output with
[jq](https://stedolan.github.io/jq/) to pass job ids to `sacct`, `squeue`,
`scancel` or `sbatch.py --afterOk`. Fixed silly bug causing `--then`,
`--else`, and `--finally` commands not to be wrapped in a script for
submission to `sbatch`.