Filter BioPerl Unrecognized DBSOURCE data warning.

[jonathancrabtree]

Filter or address the following BioPerl warning. It occurs when BioPerl parses L42023.1.gb, the H. influenzae flat file used in the gb_annotation tutorial:

--------------------- WARNING ---------------------
MSG: Unrecognized DBSOURCE data: BioProject: PRJNA219

---------------------------------------------------

Here it is in context:

$ circleator --data=L42023.1.gb --config=genes-and-percentGC-1.txt --pad=100 > hinf-genes-%gc-1.svg
INFO - started drawing figure using genes-and-percentGC-1.txt
INFO - reading from annot_file=./L42023.1.gb, seq_file=, with seqlen=

--------------------- WARNING ---------------------
MSG: Unrecognized DBSOURCE data: BioProject: PRJNA219

---------------------------------------------------
INFO - L42023: 3521 feature(s) and 1830138 bp of sequence
INFO - read 1 contig(s) from 1 input annotation and/or sequence file(s) 
INFO - finished drawing figure using genes-and-percentGC-1.txt