updating readme for docker, adding docker installation procedure
updating readme for docker, adding docker installation procedure

Hammarn/NGI-RNAseq,Hammarn/NGI-RNAseq,SciLifeLab/NGI-RNAseq,Hammarn/NGI-RNAseq,SciLifeLab/NGI-RNAseq,SciLifeLab/NGI-RNAseq,ewels/NGI-RNAseq,Galithil/NGI-RNAseq,SciLifeLab/NGI-RNAseq,Galithil/NGI-RNAseq,Hammarn/NGI-RNAseq,ewels/NGI-RNAseq,ewels/NGI-RNAseq,Hammarn/NGI-RNAseq,Galithil/NGI-RNAseq,ewels/NGI-RNAseq,Galithil/NGI-RNAseq,ewels/NGI-RNAseq,SciLifeLab/NGI-RNAseq