Make Capitalization Consistent

Some ~poorly~ configured reverse proxy interfaces are not specifically configured to respond appropriately with a lowercase "A" in the autodiscover url. So our best course is to make the capitalization consistent with the one we are used to.

data/web/autodiscover-json.php

@@ -12,7 +12,7 @@ if ($_GET['Protocol'] == 'ActiveSync') {
   echo '{"Protocol":"ActiveSync","Url":"' . $autodiscover_config['activesync']['url'] . '"}';
 }
 elseif ($_GET['Protocol'] == 'AutodiscoverV1') {
-  echo '{"Protocol":"AutodiscoverV1","Url":"https://' . $_SERVER['HTTP_HOST'] . '/autodiscover/autodiscover.xml"}';
+  echo '{"Protocol":"AutodiscoverV1","Url":"https://' . $_SERVER['HTTP_HOST'] . '/Autodiscover/Autodiscover.xml"}';
 }
 else {
   http_response_code(400);