Laravel 5.6 updates

Travis config update

Removed HHVM script as Laravel no longer support HHVM after releasing 5.3

vendor/laravelcollective/html/composer.json

@@ -18,17 +18,17 @@
         }
     ],
     "require": {
-        "php": ">=7.0.0",
-        "illuminate/http": "5.5.*",
-        "illuminate/routing": "5.5.*",
-        "illuminate/session": "5.5.*",
-        "illuminate/support": "5.5.*",
-        "illuminate/view": "5.5.*"
+        "php": ">=7.1.3",
+        "illuminate/http": "5.6.*",
+        "illuminate/routing": "5.6.*",
+        "illuminate/session": "5.6.*",
+        "illuminate/support": "5.6.*",
+        "illuminate/view": "5.6.*"
     },
     "require-dev": {
-        "illuminate/database": "5.5.*",
-        "mockery/mockery": "~0.9.4",
-        "phpunit/phpunit": "~5.4"
+        "illuminate/database": "5.6.*",
+        "mockery/mockery": "~1.0",
+        "phpunit/phpunit": "~7.1"
     },
     "autoload": {
         "psr-4": {
@@ -40,7 +40,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "5.5-dev"
+            "dev-master": "5.6-dev"
         },
         "laravel": {
             "providers": [