Added CI support.

.travis.yml

@@ -0,0 +1,15 @@
+language: php
+
+php:
+    - 7.0
+    - 7.1
+    - nightly
+
+before_install:
+    - composer self-update
+
+install:
+    - travis_retry composer install --no-interaction --prefer-source
+
+script:
+    - composer test

composer.json

@@ -22,5 +22,8 @@
     "psr-4": {
       "Cloudflare\\API\\": "src/"
     }
+  },
+  "scripts": {
+    "test": "phpunit"
   }
 }