update meta

Author: mokevnin

composer.json

@@ -1,6 +1,6 @@
 {
     "name": "hexlet/pairs",
-    "description": "",
+    "description": "Pairs implementation",
     "license": "MIT",
     "keywords": ["pairs"],
     "authors": [
@@ -9,7 +9,9 @@
             "email": "[email protected]"
         }
     ],
-    "require": {},
+    "require": {
+      "php": ">=5.3.0"
+    },
     "require-dev": {
         "phpunit/phpunit": "*",
         "squizlabs/php_codesniffer": "2.*"