check if format is fasta. Closes #523
check if format is fasta. Closes #523

bmesuere/uni-test,bmesuere/uni-test,bmesuere/uni-test,bmesuere/uni-test,unipept/unipept,unipept/unipept,unipept/unipept,unipept/unipept,unipept/unipept,bmesuere/uni-test