Add list of current makers in README.md

[tom-combet]

Is your feature request related to a problem? Please describe.
So far, user has to install the tool to discover the available makers. There is no way to know them without installing and run the listing command. He can't be sure if the tool will be useful to him or not.

Describe the solution you'd like
We should display the exhaustive list of current makers in README.md instead of the listing command.
Indicate for each maker if it comes from Symfony MakerBundle or PrestaShop Maker would be a good idea too. Also, if there are requirements (like external tools) to run the command, they have to be indicated.

Describe alternatives you've considered
N/A

Additional context
N/A