Previously the CLI would emit a warning about missing configuration
file, but a configuration file does not appear to be a requirement, at
least based on the documentation and the fact that everything can be
specified directly on the command line.
This commit simply removes the warning.
Users will no longer get a warning when doing things like `floaty
--version`, `floaty help`, and any other subcommand.
This moves the instance of the logger class to a class variable in the
`FloatyLogger` class and provides three class methods to log with in the
rest of the project `FloatyLogger.info`, `FloatyLogger.warn`, and
`FloatyLogger.error`.
