From: from@example.com
Subject: Test Email: Process
To: override@example.com
Date: [^\n]+
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="[^"]+"
Content-Transfer-Encoding: 7bit


--\S+
Date: [^\n]+
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="[^"]+"
Content-Transfer-Encoding: 7bit


--\S+
Date: [^\n]+
MIME-Version: 1.0
Content-Type: text/plain

This is a generic message: Process.

--\S+
Date: [^\n]+
MIME-Version: 1.0
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

<p>This is a generic message: <b>Process</b>.</p>=

--[^\-]+--

--[^\-]+--
