Feature/log formatting

[ellisonc]

Description

Updated common library with support for json logs and a better interface for logging the app binary and version

Migration Guide

Previously cli applications were created by calling entrypoint.NewApp(), then the application name and version were set after the fact for both the logging and the CLI description.
The new way to do this is a single call to entrypoint.NewApp(name, version)

Calling logging.GetLogger(name, version) will now return a logrus Entry instead of a logrus Logger. This entry has the name and version preset.

The behavior of the default logger is the same as in previous versions of go-commons.

A new JSON logger is available by calling logging.SetGLobalLogFormatter("json")

[MoonMoon1919]

Reviewed live w/ Andrew on a code-pairing call.

LGTM!