Move config file to `config` directory
Add config files from csscomb.php (close #91)

Add config files with sort order from previous (php) version of csscomb.
`default` is renamed to `zen`.
All other options (spaces, semicolons, etc.) are omitted.
CLI: Search for a config file recursively

Check if there is a `.csscomb.json` file in process directory.
If not, go one level up and search there.
Stop in HOME dir.
If no user's config found, take a default one from our package: `config/csscomb.json`.