[TASK] Make compatible with Composer 2.0

Author: helhum

composer.json

@@ -21,10 +21,10 @@
     },
     "require": {
         "php": ">=5.3.7",
-        "composer-plugin-api": "^1.0"
+        "composer-plugin-api": "^1.0 || ^2.0"
     },
     "require-dev": {
-        "composer/composer": "^1.1@dev",
+        "composer/composer": "^1.1@dev || ^2.0@dev",
         "mikey179/vfsstream": "~1.4.0@dev",
         "phpunit/phpunit": "^4.8"
     },

src/Plugin.php

@@ -42,6 +42,16 @@ public function activate(Composer $composer, IOInterface $io)
         $this->io = $io;
     }
 
+    public function deactivate(Composer $composer, IOInterface $io)
+    {
+        // Nothing to do
+    }
+
+    public function uninstall(Composer $composer, IOInterface $io)
+    {
+        // Nothing to do
+    }
+
     /**
      * Returns an array of event names this subscriber wants to listen to.
      *