improved logging

I've always hated how i'm logging. I want line packages , file names, methods, and line numbers. logrus doesn't provide with that info, despite a lengthy discussion (https://github.com/sirupsen/logrus/issues/63), and a pr (https://github.com/sirupsen/logrus/pull/450). I'll wait a little bit and see what happens, otherwise there are alternatives like https://github.com/inconshreveable/log15.

The issue names no files, tests, or entry points; start by locating Butler's logging setup and reviewing the referenced logrus discussion and pull request. Done would require logging package names, file names, methods, and line numbers, but the issue does not define the implementation or verification details.

Written by the indexing model from the issue text.