Add Travis CI config

Author: golonix

.travis.yml

@@ -0,0 +1,12 @@
+language: php
+
+php:
+  - 7.1
+  - 7.2
+
+before_script:
+  - curl -s http://getcomposer.org/installer | php
+  - php composer.phar install --dev --prefer-source
+
+script:
+  - php vendor/bin/phpunit