Move image and icons into images folder

Move the files out of the root and bundle into a folder
A separate icons folder is kept to make clear that the license is for
all files in that folder

Change-Id: I0c8d346c84215cfa567db9017639466e75df2b24

includes/Special/SpecialCentralAuth.php

@@ -642,7 +642,7 @@ class SpecialCentralAuth extends SpecialPage {
 			Html::element(
 				'img', [
 					'src' => $this->getConfig()->get( 'ExtensionAssetsPath' )
-						. "/CentralAuth/icons/merged-{$method}.png",
+						. "/CentralAuth/images/icons/merged-{$method}.png",
 					'alt' => $brief,
 					'title' => $brief,
 				]

includes/Special/SpecialCentralAutoLogin.php

@@ -656,7 +656,7 @@ class SpecialCentralAutoLogin extends UnlistedSpecialPage {
 			if ( $ok && $this->getConfig()->get( 'CentralAuthLoginIcon' ) && $type === 'icon' ) {
 				readfile( $this->getConfig()->get( 'CentralAuthLoginIcon' ) );
 			} else {
-				readfile( __DIR__ . '/../../1x1.png' );
+				readfile( __DIR__ . '/../../images/1x1.png' );
 			}
 		} elseif ( $type === 'json' ) {
 			header( 'Content-Type: application/json; charset=utf-8' );