Merge pull request #79 from hhxsv5/master

Optimize the required version of monolog

Author: hhxsv5

composer.json

@@ -24,7 +24,7 @@
     "ext-json": "*",
     "guzzlehttp/guzzle": "~6.0",
     "ratchet/pawl": "^0.3.2",
-    "monolog/monolog": ">=1.0"
+    "monolog/monolog": "~1.0|~2.0"
   },
   "require-dev": {
     "phpunit/phpunit": "^5.7"