Merge branch 'release/0.2.7' into develop
Command: Remove alias hash.
Add remove_all command.
Output: Print empty table.
Refactor application data, introduce migration path.
Add head command.
Fix the specs.

* Stub XDG[HOME] instead of LegacyAppData.repofile.
* Fix the default value returning in LegacyAppData.
Add specs for head.
Merge branch 'feature/head-command' into develop
Specs: Initialize AppData instead of creating the yaml file manually.
Bump version to 0.3.0
Merge branch 'release/0.3.0'