[various] Remove config/addon.config.php in favor of per-addon configuration file

piwik/README.md

@@ -30,14 +30,16 @@ Open the `config/local.config.php` file and add "piwik" to the list of activated
         ...
     ]
 
-You can change 4 more configuration variables for the addon in the `config/addon.config.php` file:
+You can change 4 more configuration variables for the addon in the `config/piwik.config.php` file:
 
-	'piwik' => [
-        'baseurl' => 'example.com/piwik/',
-        'sideid' => 1,
-        'optout' => true,
-        'async' => false,
-    ],
+	return [
+		'piwik' => [
+			'baseurl' => 'example.com/piwik/',
+			'sideid' => 1,
+			'optout' => true,
+			'async' => false,
+		],
+	];
 
 Configuration fields
 ---------------------

piwik/config/piwik.config.php

@@ -1,7 +1,7 @@
 <?php
 
 // Warning: Don't change this file! It only holds the default config values for this addon.
-// Instead overwrite these config values in config/addon.config.php in your Friendica directory
+// Instead, copy this file to config/piwik.config.php in your Friendica directory and set the correct values there
 
 return [
 	'piwik' => [

piwik/piwik.php

@@ -16,14 +16,17 @@
  *
  *   Configuration:
  *     Use the administration panel to configure the Piwik tracking addon, or
- *     in case you don't use this add the following lines to your config/addon.config.php
+ *     in case you don't use this, add the following lines to your config/piwik.config.php
  *     file:
  *
- *     [piwik]
- *     baseurl = example.com/piwik/
- *     sideid = 1
- *     optout = true ;set to false to disable
- *     async = false ;set to true to enable
+ *      return [
+ *          'piwik' => [
+ *              'baseurl' => '',
+ *              'sideid' => '',
+ *              'optout' => true,
+ *              'async' => false,
+ *          ],
+ *      ];
  *
  *     Change the siteid to the ID that the Piwik tracker for your Friendica
  *     installation has. Alter the baseurl to fit your needs, don't care
@@ -60,7 +63,7 @@ function piwik_analytics(App $a, string &$b)
 	DI::page()['htmlhead'] .= '<link rel="stylesheet"  type="text/css" href="' . DI::baseUrl()->get() . '/addon/piwik/piwik.css' . '" media="all" />';
 
 	/*
-	 *   Get the configuration variables from the config/addon.config.php file.
+	 *   Get the configuration values.
 	 */
 	$baseurl = DI::config()->get('piwik', 'baseurl');
 	$siteid  = DI::config()->get('piwik', 'siteid');