add command line options for database specs & credentials

[cyberwolf]

It would be nice if the script would accept some command line options & arguments for database host, port, name, username and password, instead of having to change the hardcoded credentials in the script.

[nicjansma]

It would certainly be a nice option to have if you're up for adding it. I've only ever had to run the script once, so having them specified on the command-line wasn't important to me. I'd set the configuration once, having gone over all of the TODOs, and ran several times in pretend mode to verify the output before running for real.

[nicjansma]

Feel free to re-open with a pull request.