README To-do item: Local commit branch behind its remote tracking branch

The problem that inspired this was:

    git fetch
    #   origin/gh-pages is now ahead of local repo's gh-pages
    git-commit-filetree gh-pages _site/
    #   gh-pages has forked because the parent of the commit we
    #   just made is not the latest commit on gh-pages from the
    #   source repo

The current workaround is to manually check out and update
(fast-forward) the local branch before going back to do our release,
which kinda kills the key feature we provide of not having to switch
one's working copy back and forth between branches.

Author: 0cjs

README.md

@@ -41,6 +41,9 @@ Missing Features
 The following features are still missing from this version of the
 program.
 
+* Deal with cases when the local branch to which we're committing is
+  behind its remote tracking branch. Normally we'd want the local branch
+  to be fast-forwarded to match the remote before doing our commit.
 * Update the reflog after doing the commit.
 * Add the ability to specify a commit message.
   (This should allow a token to substitute the current HEAD commit at