Added composer.json for the Composer pack. system

Now, PHP Free Chat can be distributed via composer packaging system.

Author: pavelsmolka

composer.json

@@ -0,0 +1,9 @@
+{
+    "name": "kerphi/phpfreechat",
+    "description": "A simple web based chat",
+    "homepage": "http://www.phpfreechat.net/",
+    "require": {
+        "php": ">=5.3.0",
+        "slim/slim": "2.*"
+    },
+}