Is it possible to set branch permissions using git bash? I would like to have much more strict permissions on the master branch, so that some people can use the development
Git does not have branch specific permissions. You can either make the whole repository read only to the people or create one private and one public repository and only push the development branch to the public on while keeping the master only in your private repository.
Edit: For branch specific permissions, you need a server-side authorization layer like Gitolite — obviously, this requires you to be managing your own Git server.