Add Dockerfiles for each application step

[susheel]

@scapella Please add the Dockerfiles following applications into the /containers folder for reproducibility.

• [ ] cutadapt (v.1.18) --> /containers/cutadapt/v.1.18/Dockerfile
• [ ] bwa-mem (v.0.7.17) --> /containers/bwa-mem/v.0.7.17/Dockerfile
• [ ] Sambamba (v.0.6.8 ) --> /containers/Sambamba/v.0.6.8/Dockerfile
• [ ] Picard (v.2.18.25) --> /containers/Picard/v.2.18.25/Dockerfile
• [ ] GATK (v.3.6-0) --> /containers/GATK/v.3.6-0/Dockerfile
• [ ] fastqc (v.0.11.8) --> /containers/fastqc/v.0.11.8/Dockerfile

Please cross-ref the original Dockerfile if available.

[rtonda]

We added our version in the containers folder