adding composer manifest to distribute as a library

Author: Mark Rickerby

composer.json

@@ -0,0 +1,16 @@
+{
+    "name": "chrisboulton/php-diff",
+	"type": "library",
+    "description": "A comprehensive library for generating differences between two hashable objects (strings or arrays).",
+    "authors": [
+        {
+            "name": "Chris Boulton",
+            "email": "@chrisboulton"
+        }
+    ],
+	"autoload": {
+		"psr-0": {
+		   "Diff": "lib/"
+		}
+	}
+}