title: git filter-repo: can it be used on a specific branch?
body: <p>I'm reading about what <code>git filter-repo</code> can do because I want to do a small experiment with it.... I have this repo where I only want to get the history of one directory from, say.... master..... but I don't want to work on master. I would like to create a new branch, say <code>filter-repo-test</code> and let <code>git filter-repo</code> run its magic on this branch alone. I'm reading the manual but I don't see an option to specify only a given branch. Is it possible?</p>
  
  <p><a href="https://htmlpreview.github.io/?https://github.com/newren/git-filter-repo/blob/docs/html/git-filter-repo.html" rel="noreferrer">https://htmlpreview.github.io/?https://github.com/newren/git-filter-repo/blob/docs/html/git-filter-repo.html</a></p>