add simple kallisto wrappers and workflow

[mr-c]

For @alaincoletta

Inspired by https://github.com/InSilicoDB/pipeline-kallisto/blob/develop/main.nf

To run:

git clone https://github.com/common-workflow-language/workflows.git --branch kallisto
virtualenv cwl
source cwl/bin/activate
pip install cwlref-runner
cd workflows/workflows
# download your data
cwl-runner kallisto-demo.cwl --transcripts path/to/transcripts.fasta --reads path/to/first-reads.fastq --reads path/to/second-reads.fastq
# verify the output
ls -l abundance.h5