added log4php as a dependency for composer

README

@@ -45,10 +45,6 @@ Just add the package "marcelog/ding":
         "marcelog/ding": "dev-master"
     }
 }
-
-Note that since log4php is a dependency and does not have a composer
-installation available, you will need to add it to your own composer.json file.
-
 Packagist URL: http://packagist.org/packages/marcelog/ding
 -------------------------------------------------------------------------------
 Available via PEAR

composer.json

@@ -13,12 +13,18 @@
       "role": "Developer"
     }
   ],
+  "repositories": [
+  {
+    "type": "pear",
+    "url": "http://pear.apache.org/log4php/"
+  }],
   "autoload": {
     "psr-0": {
       "Ding": "src/mg"
     }
   },
   "require": {
-    "php": ">=5.3.3"
+    "php": ">=5.3.3",
+    "pear-log4php/Apache_log4php": ">=2.1.0"
   }
 }