Allow overwriting the fpm pools config name via 'filename'.

[jochumdev]

I need this for the mongo ext_pillar.

https://rene.jochums.at/howto-move-saltstack-tops-and-pillar-contents-to-mongodb https://rene.jochums.at/having-fun-with-saltstack-and-ext_pillar-mongo

Signed-off-by: Rene Jochum rene@jochums.at

[gravyboat]

Thanks.