Go CleanArch 1.2.0

This release demonstrates two major features.
First, how mutable settings may be persisted in a database, loaded during the system start up (overriding the configuration file settings), and managed during a multi-database migration operation. Concepts of visible and invisible and mutable and immutable settings are also described.
Second, comments which are written in the YAML configuration files are now preserved when a new configuration file is written by a migration.