How set default outputer in .pepperrc

[terentev-mn]

Hi! Pepper is very cool tool for delegate/manage rights access to salt
It would be nice if it was able set default output format in config file.

[gtmanfred]

This is not currently possible, and the config file is only meant to store information about how to connect to the salt api, so it would require a pretty big reworking of how the options work in pepper.

A PR with some tests would be welcome though.