Add dev_commit.sh helper and no-emoji mandate

wp-includes/class-smtp.php

@@ -0,0 +1,15 @@
+<?php
+
+/**
+ * The SMTP class has been moved to the wp-includes/PHPMailer subdirectory and now uses the PHPMailer\PHPMailer namespace.
+ */
+_deprecated_file(
+	basename( __FILE__ ),
+	'5.5.0',
+	WPINC . '/PHPMailer/SMTP.php',
+	__( 'The SMTP class has been moved to the wp-includes/PHPMailer subdirectory and now uses the PHPMailer\PHPMailer namespace.' )
+);
+
+require_once __DIR__ . '/PHPMailer/SMTP.php';
+
+class_alias( PHPMailer\PHPMailer\SMTP::class, 'SMTP' );