Db name fix (pt. 2)

[davla]

Original one here: https://github.com/worron/ACYLS/pull/16

I'm sorry pal, but I didn't test properly and it didn't work. I've tested now in these scenarios, tell me if you come up with anything else:

• No GNU dbm implementation installed, so ndbm is forced. Both save and load. :heavy_check_mark:
• GNU dbm installed, both save and reload of GNU dbm databases. :heavy_check_mark:
• With GNU dbm installed, load a NDBM file (the one generated previously). :heavy_check_mark:
• With no GNU dbm installed, load a GNU dbm database. Fails to load it, with proper error message about dbm.gnu module missing. :heavy_check_mark:

[worron]

No problem.