PostgreSQL support. Configure options array. Issue #10 resurrected: custom jobs table name.

[jfloff]

Decided to implement couple of stuff, here's a breakdown:

• PostgreSQL support: Generalize some MySQL specific code to work on both db engines. Created a new .sql file to create a PostgreSQL jobs table and a specific test file.
• Implemented configure to take options array: Was on the todo list of the repository. At the same time, revamped the connection parameters to be more generic (no need for specific MySQL type of connection parameters anymore).
• Resurrected issue Let me know if this solution works for you. I am happy to go another route if you like. #10: Since I was at it, thought this one was worth the effort ;)
• I also added a .gitignore file .

SQLite support is something that I though could be useful, but early investigations lead me to delay it, due to possible heavy changes in SQL code (bulk INSERT's mainly).

EDIT:
If you want me to rebase to one commit please say so.
Typos.

[josegonzalez]

I'm worried about that bc change, which could end up breaking existing installations - such as our own! - so I'm not going to merge this in without further explanation.

Apologies for taking so much time to get to this.

[jfloff]

Really sorry I didn't document that well.

Hope my explanation brings some light into why I went that route. I can gladly try to change this to be BC.

No apologies needed :)

[josegonzalez]

I'd rather revert any bc changes and then have a separate commit that brings in postgres support.

You may need to rebase your commit as I've recently updated the tests and some retry code was added.

[jfloff]

I'll do that then. Will do a first commit for everything except postgres. Then will commit postgres support.

Kudos

[jfloff]

Heres the commit without postgres support. Hope that alright. I'll now take a look at postgres support without breaking BC.

[josegonzalez]

use spaces before the first parens and use {} for codeblocks.

[josegonzalez]

Thanks for the pr!