YAML support for configuration

[danvergara]

Description

According to #120, add other formats for configurations would be helpful for non-python programmers/projects. I've seen that YAML is a quite adopted format. As a Golang programmer, I could say that YAML is mainly used for actual configuration and its use is encouraged by the community. As a Docker user, I always add a docker-compose.yml file to set up my local containers.

Possible Solution

Add a new class called YamlConfig or YAMLConfig besides the current TomlConfiguration, to parse either .cz.yaml or cz.yaml config files provided by the user. This could enrich the configuration options along with the json support proposed in this #313 PR.

Related Issue

#120