as part of the generated .zip/git repo, create a file with relevant metadata

[Ladicek]

In a discussion with @cmoulliard, we came up with an idea: the Launcher could generate, in the root directory of the .zip / Git repo, a file called e.g. .launched-from (or .launcher-metadata, or whatever). This file would contain relevant metadata to how the .zip / Git repo was generated: parameters selected in the wizard, the original booster Git repo and tag, etc. It would be useful when reporting a booster issue. Format of the file could be YAML, JSON, Java properties, etc.