v2 version-branch workflow

[rasmusei]

• Main branch is named to legacy branch (for backup) in all repos
• Stage is renamed to main branch in all repos
• Current dev branch will be named v3.3.1 in all repos
• Repo default branch should be set to main in all repos

[tonisostrat]

If there are also files in the repo(s) that contain the version number then make sure those correspond to the branch name