add travis-ci configuration

Author: arkadiusjonczek

.travis.yml

@@ -0,0 +1,21 @@
+language: php
+
+sudo: false
+
+php:
+  - 5.3
+  - 5.4
+  - 5.6
+  - 7.0
+  - 7.1
+  - 7.2
+  - nightly
+
+cache:
+  directories:
+    - $HOME/.composer/cache
+
+before_script:
+  - composer install
+
+script: composer test

README.md

@@ -66,4 +66,10 @@ Now, run PHPUnit Tests.
 
 ```bash
 vendor/bin/phpunit
+```
+
+Or use composer.
+
+```bash
+composer test
 ```

composer.json

@@ -25,5 +25,10 @@
         "psr-4": {
             "BabyMarkt\\DeepL\\": "tests/"
         }
+    },
+    "scripts": {
+        "test": [
+          "vendor/bin/phpunit"
+        ]
     }
 }