title: safe character to separate multiple urls
body: <p>I am preparing a special string, in which keys are values are concatenated like below:</p>
  
  <pre><code>username=foo&amp;age=24&amp;email=foo@bar.com&amp;homepage=http://foo.com
  </code></pre>
  
  <ul>
  <li>&amp; is the separator for two key=value pairs</li>
  <li>value is url encoded</li>
  </ul>
  
  <p>I have a scenario where there are multiple home pages for a user. 
  I want to specify multiple urls for the homepage key</p>
  
  <pre><code>name=foo&amp;age=24&amp;email=foo@bar.com&amp;homepage=url1&lt;some_safe_url_separator_char&gt;url2&lt;some_safe_url_separator_char&gt;url3
  </code></pre>
  
  <ul>
  <li>We have no control/idea over what url1, url2, .. may contain?</li>
  </ul>
  
  <p>What is a good choice of some_safe_url_separator_char?<br><br>
  In other words I am not looking for a safe character to be used IN a url, but a safe character to be used to SEPARATE two urls in a string</p>