Commit Message Format

Each commit message consists of a header, a body and a footer. The header has a special format that
includes a type, a scope and a subject:

<type>(<scope>): <subject>
<BLANK LINE>
<body>
<BLANK LINE>
<footer>

The header is mandatory and the scope of the header is optional.

Any line of the commit message cannot be longer 100 characters! This allows the message to be easier
to read on GitHub as well as in various git tools.

Footer should contain a closing reference to an issue if any.

This leads to more readable messages that are easy to follow when looking through the project history.
But also, the git commit messages can be used to generate the changelog.
