build: Update and formalise copyright notice

* Sync the copyright statements between:
  - the initial php-cssjanus commit (which predates the Node.js version
    becoming upstream instead of downstream).
  - the LICENSE.txt file.
  - the CSSJanus.php file.

* Copy it to the NOTICE.txt file, as expected by the terms of the
  Apache 2.0 license.

* Move list of principal authors to AUTHORS.txt.

* Add several more major contributors based on `git shortlog -se | sort -rn`.

* Add CODE_OF_CONDUCT.md, previously missing.

* Fix code.google.com deadlink, and move to README.md.

* Update outdated self-description in CSSJanus.php, this is now
  a port of the Node.js version.

Author: Krinkle

.mailmap

@@ -0,0 +1,3 @@
+Ed Sanders <ejsanders@gmail.com>
+James Forrester <jforrester@wikimedia.org>
+Matthew Flaschen <mflaschen@wikimedia.org>

AUTHORS.txt

@@ -0,0 +1,10 @@
+Principal authors and major contributors (alphabetically):
+
+Bryon Engelhardt <ebryon77@gmail.com>
+Ed Sanders <ejsanders@gmail.com>
+James Forrester <jforrester@wikimedia.org>
+Lindsey Simon <elsigh@google.com>
+Roan Kattouw <roankattouw@gmail.com>
+Roozbeh Pournader <roozbeh@gmail.com>
+Timo Tijhof <krinklemail@gmail.com>
+Trevor Parscal <trevorparscal@gmail.com>

CODE_OF_CONDUCT.md

@@ -0,0 +1 @@
+This project adheres to the [Wikimedia Code of Conduct](https://www.mediawiki.org/wiki/Code_of_Conduct).

NOTICE.txt

@@ -0,0 +1,18 @@
+PHP port of CSSJanus. https://github.com/cssjanus/php-cssjanus
+
+Copyright 2020 Timo Tijhof
+Copyright 2014 Trevor Parscal
+Copyright 2010 Roan Kattouw
+Copyright 2008 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

README.md

@@ -44,10 +44,10 @@ If a rule is not meant to be flipped by CSSJanus, use a `/* @noflip */` comment
 
 ## Port
 
-This is a PHP port of the Node.js implementation of CSSJanus.
+This is a PHP port of the Node.js implementation of CSSJanus, and was originally
+based on a [Google project](http://code.google.com/p/cssjanus/).
 
-Feature requests and bugs related to the actual CSS transformation or test
-cases of it, should be submitted upstream at
-<https://github.com/cssjanus/cssjanus>.
+Feature requests and bugs related to the actual CSS transformation logic or test
+cases of it, should be submitted upstream at <https://github.com/cssjanus/cssjanus>.
 
 Upstream releases will be ported here.

composer.json

@@ -4,10 +4,10 @@
 	"license": "Apache-2.0",
 	"authors": [
 		{
-			"name": "Trevor Parscal"
+			"name": "Roan Kattouw"
 		},
 		{
-			"name": "Roan Kattouw"
+			"name": "Trevor Parscal"
 		},
 		{
 			"name": "Timo Tijhof"

src/CSSJanus.php

@@ -1,10 +1,11 @@
 <?php
 /**
- * PHP port of CSSJanus.
- * https://github.com/cssjanus/php-cssjanus
+ * PHP port of CSSJanus. https://github.com/cssjanus/php-cssjanus
  *
- * Copyright 2008 Google Inc.
+ * Copyright 2020 Timo Tijhof
+ * Copyright 2014 Trevor Parscal
  * Copyright 2010 Roan Kattouw
+ * Copyright 2008 Google Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,13 +23,8 @@
  */
 
 /**
- * This is a PHP port of CSSJanus, a utility that transforms CSS style sheets
- * written for LTR to RTL.
- *
- * Original code: http://code.google.com/p/cssjanus/source/browse/trunk/cssjanus.py
- *
- * @author Lindsey Simon <elsigh@google.com>
- * @author Roan Kattouw
+ * CSSJanus is a a utility that converts CSS stylesheets
+ * from left-to-right (LTR) to right-to-left (RTL).
  */
 class CSSJanus {
 	// Patterns defined as null are built dynamically by buildPatterns()
@@ -476,7 +472,6 @@ private static function calculateNewBackgroundPosition($matches) {
 /**
  * Utility class used by CSSJanus that tokenizes and untokenizes things we want
  * to protect from being janused.
- * @author Roan Kattouw
  */
 class CSSJanusTokenizer {
 	private $regex;