* Remove d2config.Config singleton
* refactored config file bootstrap
* `d2loader.Loader` adds the config directories during init
* `d2asset.AssetManager` loads the config file during init
* mpq verification logic removed from d2config; this is done by d2loader
* added `errorMessage` to `d2app.App` for setting the error message for the error screen.
* fixed loader test
* refactored logging in d2config, d2record, and d2asset
* asset manager, record manager, and file loader now utilitize d2util.Logger
* added colored logging to d2util.Logger (excluding windows platforms)
* removed mpq file verification from d2config; d2loader handles this
* record loaders now use the record manager's logger for printing info
* added command line argument for setting log level (`--loglevel 4`, `-l4`, or `-l 4`
* added `LogLevel` parameter to config file
* default log level will show errors, warnings, and info log messages
* specifying log level as an argument overrides setting from config file
* fixed log level tests
