php8 support (#4)

* php8 support

* travis php8

Author: shatkovskiy

.travis.yml

@@ -31,6 +31,13 @@ matrix:
           env: LARAVEL_VERSION=~7.0  TESTBENCH_VERSION=~5.0  PHPUNIT_VERSION=~9.0
         - php: 7.4
           env: LARAVEL_VERSION=~8.0  TESTBENCH_VERSION=~6.0  PHPUNIT_VERSION=~9.0
+          
+        - php: 8.0
+          env: LARAVEL_VERSION=~6.0  TESTBENCH_VERSION=~4.0  PHPUNIT_VERSION=~8.0
+        - php: 8.0
+          env: LARAVEL_VERSION=~7.0  TESTBENCH_VERSION=~5.0  PHPUNIT_VERSION=~9.0
+        - php: 8.0
+          env: LARAVEL_VERSION=~8.0  TESTBENCH_VERSION=~6.0  PHPUNIT_VERSION=~9.0
 
 before_install:
     - travis_retry composer self-update

composer.json

@@ -19,7 +19,7 @@
         }
     ],
     "require": {
-        "php": "^7.2",
+        "php": "^7.2|^8.0",
         "ext-zip": "*",
         "illuminate/contracts": "^6.0|^7.0|^8.0",
         "illuminate/support": "^6.0|^7.0|^8.0"