title: Git-flow fails with "fatal: no tag message? / Tagging failed. Please run finish again to retry"
body: <p>I am using <a href="https://github.com/nvie/gitflow">git-flow</a> to manage a project.  I am getting the following message when issuing <code>git flow release 
  finish foo</code>:</p>
  
  <pre><code>fatal: no tag message? 
  Tagging failed. Please run finish again to retry. 
  </code></pre>
  
  <p>Here is the sequence of steps to reproduce, with a brand new git 
  repository and a single file: </p>
  
  <pre><code>touch test.txt 
  git init 
  git add . 
  git commit -m "Initial commit" 
  git flow init 
  [defaults accepted] 
  git flow release start 1.0 
  echo "Line 1" &gt;&gt; test.txt 
  git add . 
  git commit -am "Line added" 
  git flow release finish '1.0' 
  </code></pre>
  
  <p>At this point, error message above pops up, and Vim is called up to 
  add a tag.  When I add the tag and save, I end up on the master 
  branch, with the release/1.0 branch still existing.  Any ideas what is 
  going wrong?  Git flow version is 0.4.1. </p>
  
  <p>Thank you.</p>