title: set textwidth in vim without overriding filetype specific
body: <p>I would like a textwidth of 80 by default in vim, but if specific filetypes have their own text width (in particular gitcommit where tw=72) I would like vim to honour that width.</p>
  
  <p>In my .vimrc I have the line:</p>
  
  <pre><code>set tw=80
  </code></pre>
  
  <p>I have also tried </p>
  
  <pre><code>setlocal tw=80
  </code></pre>
  
  <p>However this seems to override the gitcommit width of 72.</p>
  
  <p>If I remove the line then git commits work fine (wrap at 72) but a text file (for example) will not wrap automatically.</p>
  
  <p>Is it possible to have vim wrap to 80 if nothing else is specified, but otherwise follow the specific filetype instructions?</p>
  
  <p>As an aside, I think this used to work up until recently.  I have tried removing everything else from my .virmrc but the set tw=80, but this doesn't make any difference.</p>
  
  <p><strong>EDIT</strong>:  If I open up a git commit message editor, and run </p>
  
  <p><code>:verbose set tw?</code></p>
  
  <p>vim displays:</p>
  
  <pre><code>   textwidth=80
          Last set from ~/.vimrc
  </code></pre>