add support to monolog v2

Author: cesargb

composer.json

@@ -23,7 +23,7 @@
         "illuminate/console": "~5.5.28 | ^5.6 | ~6.0.0",
         "illuminate/log": "~5.5.28 | ^5.6 | ~6.0.0",
         "illuminate/support": "~5.5.28 | ^5.6 | ~6.0.0",
-        "monolog/monolog": "~1.20"
+        "monolog/monolog": "~1.20|^2.0"
     },
     "require-dev": {
         "orchestra/testbench": "^3.5 | ^4.0",