title: Make Django build-in send_mail function working with html by default
body: <p>I want to substitute build-in <strong>send_mail</strong> function, that works only with plain-text emails, with my own smart <strong>send_mail</strong> function, that generates both html and plain-text versions automatically. Everything works as expected for my own emails, defined in my own application. I can do it in views.py in this fashion:</p>
  
  <pre><code>from django.core import mail
  from utils import send_mail as send_html_mail
  mail.send_mail = send_html_mail
  </code></pre>
  
  <p>But the problem still appears with emails of third-side applications. There all imports already completed before my code with monkey-patching of <strong>send_mail</strong> function. </p>
  
  <p>Is it possible to override this function before all imports of all django applications? Or may be there is another solution of this issue. I really don't want to patch code with sending emails of these third-party applications. It's much easy just to put html-template.</p>