title: What are the possible values of regconfig in postgresql?
body: <ol>
  <li><p><a href="http://www.postgresql.org/docs/9.3/static/textsearch-controls.html" rel="noreferrer">http://www.postgresql.org/docs/9.3/static/textsearch-controls.html</a> often refers to an optional <strong>regconfig</strong> parameter, but I can't find its possible values and their meanings. Where is it documented? If this can't be answered (e.g. because it depends on my installed database-components or like), how can I determine it myself?</p></li>
  <li><p>I'd like a "plain text" regconfig, without any human-language transformation. What is the argument for it?</p></li>
  </ol>