File based hierarchy configuration

[hielfx]

Motivation

Currently we have only one configuration file located in the user's home directory. A better approach would be to create a file hierarchy for each supported operating system, so the users could have different configurations for each projects, with a general one.

This configuration should be merged (instead of replaced) so the users can override some of the configuration options.

Example of hierarchy:

1. Environment variable
2. Project
3. Home
4. System
5. ...

Acceptance criteria

• [ ] Users can define several configurations files and they are merged on a hierarchical manner.
• [ ] Configuration is merged and override some of the field, instad of all of them.