Bugfix tabs in fasta header
A colleague built a pangenome containing tab characters in the fasta header of one of the genome files. It appears this is a problem to the databases/genome.db/sequences.info file, which contains full fasta headers with information in a TSV format.
Best solution seems to me to check each fasta header when running build_pangenome or add_genomes for tabs, and throw an exception if this is case. This is implemented here.