Add support for Laravel 5.1 & 5.2

Author: gregoriohc

composer.json

@@ -12,11 +12,11 @@
         }
     ],
     "require": {
-        "php": ">=5.6.4",
+        "php": ">=5.5.9",
         "twilio/sdk": "^4.11",
-        "illuminate/notifications": "5.3.*",
-        "illuminate/support": "5.3.*",
-        "illuminate/events": "5.3.*"
+        "illuminate/notifications": "5.1.*|5.2.*|5.3.*",
+        "illuminate/support": "5.1.*|5.2.*|5.3.*",
+        "illuminate/events": "5.1.*|5.2.*|5.3.*"
     },
     "require-dev": {
         "mockery/mockery": "^0.9.5",
@@ -37,7 +37,5 @@
     },
     "config": {
         "sort-packages": true
-    },
-    "minimum-stability": "dev",
-    "prefer-stable": true
+    }
 }