Add well-known Thunderbird autoconfig XML

In prod since 2020-06-17 05:01:53 -0700 (at least).

Author: strugee

src/misc/well-known/autoconfig/mail/config-v1.1.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<clientConfig version="1.1">
+  <emailProvider id="strugee.net">
+    <domain>strugee.net</domain>
+    <displayName>strugee.net mail service</displayName>
+    <displayShortName>strugee.net</displayShortName>
+    <incomingServer type="imap">
+      <hostname>imap.strugee.net</hostname>
+      <port>143</port>
+      <socketType>STARTTLS</socketType>
+      <authentication>password-cleartext</authentication>
+      <username>%EMAILADDRESS%</username>
+    </incomingServer>
+    <outgoingServer type="smtp">
+      <hostname>smtp.strugee.net</hostname>
+      <port>587</port>
+      <socketType>STARTTLS</socketType>
+      <authentication>password-cleartext</authentication>
+      <username>%EMAILADDRESS%</username>
+    </outgoingServer>
+  </emailProvider>
+</clientConfig>