Moved phinx from required deps to suggestions

Author: Nikita Chernyi

composer.json

@@ -8,9 +8,11 @@
         "ext-pdo": "*",
         "wtf/core": "^1.1.6",
         "catfan/medoo": "@stable",
-        "robmorgan/phinx": "@stable",
         "respect/validation": "^1"
     },
+    "suggest": {
+        "robmorgan/phinx": "Database migrations and seeds",
+    },
     "autoload": {
         "psr-4": {
             "Wtf\\ORM\\": "src/"