Document the adjustment workflow and warn users about adjusting old MySQL

Summary: Ref T1191. Explain the adjustment workflow, how to resolve common errors, etc.

Test Plan: Read it, clicked doc links.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T1191

Differential Revision: https://secure.phabricator.com/D10758

src/applications/config/controller/PhabricatorConfigDatabaseIssueController.php

@@ -133,10 +133,6 @@ final class PhabricatorConfigDatabaseIssueController
 
     $errors = array();
 
-    $errors[] = pht(
-      'IMPORTANT: This feature is in development and the information below '.
-      'is not accurate! Ignore it for now. See T1191.');
-
     if (isset($counts[PhabricatorConfigStorageSchema::STATUS_FAIL])) {
       $errors[] = pht(
         'Detected %s serious issue(s) with the schemata.',
@@ -152,7 +148,7 @@ final class PhabricatorConfigDatabaseIssueController
     $title = pht('Database Issues');
 
     $table_box = id(new PHUIObjectBoxView())
-      ->setHeaderText($title)
+      ->setHeader($this->buildHeaderWithDocumentationLink($title))
       ->setFormErrors($errors)
       ->appendChild($table);