updated minimum php version to 7.0

Author: msonowal

composer.json

@@ -12,9 +12,9 @@
         }
     ],
     "require": {
-        "php": ">=5.6.4",
-        "illuminate/notifications": "^5.3|^5.4|^5.5|^5.6|^5.7|^5.8|^6.0",
-        "illuminate/support": "~5.5||~6.0"
+        "php": ">=7.0",
+        "illuminate/notifications": "~5.5|~6.0",
+        "illuminate/support": "~5.5|~6.0"
     },
     "require-dev": {
         "mockery/mockery": "^0.9.5|^1.0",