New module FarNet.GitKit

[nightroman]

https://github.com/nightroman/FarNet/tree/main/GitKit/README.md

GitKit is the new FarNet module for git operations in Far Manager.
GitKit uses LibGit2Sharp and does not require installed git.

For now GitKit provides three panels with basic operations:

• Branches
• Commits
• Changes

TODO: support more commands for everyday basic tasks.