Update README with note about no working directory

If you run the commands listed in usage

```bash
  mkdir repo-git # or whatever
  cd repo-git
  git init
  hg-fast-export.sh -r <repo>
```

you are not given a working directory to start working in. I was
caught off-guard by this when I ran `git status` and everything in the
repo was listed as deleted. A quick google search indicates I'm not
the only one who was surprised.

diff --git a/README b/README
index e8e855c..99fde49 100644 (file)
--- a/README
+++ b/README
@@ -20,6 +20,10 @@ Using hg-fast-export is quite simple for a mercurial repository <repo>:
   git init
   hg-fast-export.sh -r <repo>
 
+Please note that hg-fast-export does not automatically check out the
+newly imported repository. You probably want to follow up the import
+with a "git checkout"-command.
+
 Incremental imports to track hg repos is supported, too.
 
 Using hg-reset it is quite simple within a git repository that is