Added support for piping in gzipped VCF via zcat
Added support for piping in gzipped VCF via zcat

Ensembl/ensembl-variation,dbolser/ensembl-variation,dbolser-ebi/ensembl-variation,dbolser-ebi/ensembl-variation,dbolser/ensembl-variation,dbolser/ensembl-variation,Ensembl/ensembl-variation,willmclaren/ensembl-variation,Ensembl/ensembl-variation,willmclaren/ensembl-variation,Ensembl/ensembl-variation,dbolser-ebi/ensembl-variation,willmclaren/ensembl-variation,Ensembl/ensembl-variation,willmclaren/ensembl-variation,willmclaren/ensembl-variation,dbolser/ensembl-variation