📝 (scripts) Add documentation for sugar scripts

[jmaupetit]

Purpose

Our development environment relies on Docker and docker-compose, leading to permission issues on HOST while working on the project. To solve these kind of issues and ease developer on-boarding on the project, we wrote a bunch of shell scripts (bash) to build, run and test Fonzie.

Even if those scripts are relevant to improve the developer experience, they raise two kind of problems we need to address:

1. wrapping docker(-compose) commands can appear unnecessary for advanced users that prefer using docker raw commands,
2. hiding the underlying docker complexity will not incentive new users to learn it from the basis.

Proposal

We need to exhaustively document those scripts to explain what they are doing (by comparing them with docker(-compose) raw commands) and how they can ease the developer life.

[jmaupetit]

I think, this issue needs an update since many things will change after #11 will have been implemented.