Merge pull request #14 from repzy/extend-php-version

extend php version

Author: petrkotek

.travis.yml

@@ -1,7 +1,8 @@
 language: php
 
 php:
-  - "7.1"
+  - "7.2"
+  - "8.0"
 
 install:
   - composer install --no-interaction

composer.json

@@ -17,10 +17,10 @@
         }
     },
     "require": {
-        "php": "^7.1"
+        "php": ">=7.2"
     },
     "require-dev": {
-        "phpunit/phpunit": "^7.0",
+        "phpunit/phpunit": "^8.5",
         "satooshi/php-coveralls": "^1.0"
     }
 }