Define some technical specifications for the git project sharing

The goal is to allow our customer and us to get the studio project's sources.
We need to define how it's used by studio:

• is it a direct usage
• is it synced
• does it require any validation
• what's synced (branches, tags)
• what's removed on sync (branches, tags)
• what about the existing workspaces whose content would not be valid anymore (in case of rebase/cherry-pick for example)