Add monolog dep as required

Dan Richelson · Dan Richelson · commit f6fd57d4299e · 2016-11-08T12:41:26.000-08:00
diff --git a/composer.json b/composer.json
@@ -14,6 +14,7 @@
         }
     ],
     "require": {
+        "monolog/monolog": "1.21.0",
         "php": ">=5.5",
         "psr/log": "1.0.0"
     },
