Changing requirements adding PSR/LOG

composer.json

@@ -11,7 +11,8 @@
     "php": "^7.1",
     "ext-hash": "*",
     "ext-curl": "*",
-    "ext-json": "*"
+    "ext-json": "*",
+    "psr/log": "1.1.*"
   },
   "autoload": {
     "psr-4": {