Beautify the CLI

[thw26]

Following #161 we should aim to beautify the CLI, such as making sure we have proper newlines and even adding color prompts.

Some resources:

• https://stackoverflow.com/questions/287871/how-do-i-print-colored-text-to-the-terminal
• https://github.com/termcolor/termcolor
• https://sentry.io/answers/print-colored-text-to-terminal-with-python/
• https://nochlin.com/blog/6-techniques-i-use-to-create-a-great-user-experience-for-shell-scripts

cf. ferion11/LogosLinuxInstaller#185