Add metrics to CLI

## Overview
Introduce matrices in the CLI. Every time it executes it raises an event that is send to mixpanel.

## What still needs to be done
This is still a naive implementation. It doesn't contain any automated tests and the calls to mixpanel are blocking.

## Fixes also
This pull request also contains a few other bug fixes:

1. Wrong mocking for validation command tests
2. Fix infinitive loop for user name retrieval