Modified namedb.py and annotate-seqs.py to work with files supplied via command line to annotate-seqs.py

mouse.namedb, mouse.namedb.fullname and mouse.protein.faa were hardcoded into namedb.py.
Now, it picks up from sys.argv[4] and sys.argv[5], where sys.argv is supplied to
annotate-seqs.py

Possible regression bugs if namedb.py is used by scripts other than annotate-seqs.py
that use a different command line argument pattern