title: How to store a git config as part of the repository?
body: <p>I'm using filters to mangle files during checkout like described <a href="https://git-scm.com/book/en/v2/Customizing-Git-Git-Attributes#Keyword-Expansion" rel="noreferrer">here</a>.
  Now the problem is that filter definition is only stored in my local configuration file:</p>
  
  <pre><code>$ cat .git/config
  ....
  [filter "dater"]
          smudge = /home/.../expand_date
          clean = perl -pe \"s/\\\\\\$Date[^\\\\\\$]*\\\\\\$/\\\\\\$Date\\\\\\$/\"
  </code></pre>
  
  <p>If my coworkers want to benefit from this <code>Date</code> expansion, they need to copy my filter definition. And if I change it, I need to notify them, etc..</p>
  
  <p>So can I store this filter definition part of <code>.git/config</code> in repository and make git use it?</p>