Change default fasta_fields to match default GISAID output.
Change default fasta_fields to match default GISAID output.

@rneher: please revert if you disagree

blab/stability,blab/stability,doerlbh/Indie-nextflu,blab/nextflu,doerlbh/Indie-nextflu,fw1121/nextflu,blab/stability,doerlbh/Indie-nextflu,blab/nextflu,fw1121/nextflu,blab/nextflu,fw1121/nextflu,doerlbh/Indie-nextflu,fw1121/nextflu,blab/stability,blab/nextflu,blab/stability,blab/nextflu,blab/stability