Add SO Installer

Author: AlexGStapleton

.gitmodules

@@ -1,3 +1,7 @@
 [submodule "build"]
 	path = build
 	url = [email protected]:siteorigin/plugin-build.git
+
+[submodule "inc/installer"]
+	path = inc/installer
+	url = [email protected]:siteorigin/siteorigin-installer.git

inc/admin.php

@@ -64,6 +64,11 @@ public function __construct() {
 		// Check to make sure we have all the correct markup.
 		SiteOrigin_Panels_Admin_Dashboard::single();
 
+		// Load the Installer If it's not already active.
+		if ( ! class_exists( 'SiteOrigin_Installer' ) ) {
+			include plugin_dir_path( __FILE__ ) . 'installer/siteorigin-installer.php';
+		}
+
 		$this->in_save_post = false;
 
 		// Enqueue Yoast compatibility