Added travis ci config file

Author: korridor

.travis.yml

@@ -0,0 +1,38 @@
+cache:
+  directories:
+    - $HOME/.composer/cache
+
+language: php
+
+matrix:
+  include:
+    - php: 7.2
+      env: LARAVEL='5.8.*' TESTBENCH='3.8.*' COMPOSER_FLAGS='--prefer-lowest'
+    - php: 7.2
+      env: LARAVEL='5.8.*' TESTBENCH='3.8.*' COMPOSER_FLAGS='--prefer-stable'
+    - php: 7.3
+      env: LARAVEL='5.8.*' TESTBENCH='3.8.*' COMPOSER_FLAGS='--prefer-lowest'
+    - php: 7.3
+      env: LARAVEL='5.8.*' TESTBENCH='3.8.*' COMPOSER_FLAGS='--prefer-stable'
+    - php: 7.2
+      env: LARAVEL='6.*' TESTBENCH='4.*' COMPOSER_FLAGS='--prefer-lowest'
+    - php: 7.2
+      env: LARAVEL='6.*' TESTBENCH='4.*' COMPOSER_FLAGS='--prefer-stable'
+    - php: 7.3
+      env: LARAVEL='6.*' TESTBENCH='4.*' COMPOSER_FLAGS='--prefer-lowest'
+    - php: 7.3
+      env: LARAVEL='6.*' TESTBENCH='4.*' COMPOSER_FLAGS='--prefer-stable'
+  fast_finish: true
+
+before_script:
+  - composer config discard-changes true
+
+before_install:
+  - travis_retry composer self-update
+  - travis_retry composer require "laravel/framework:${LARAVEL}" "orchestra/testbench:${TESTBENCH}" --no-interaction --no-update
+
+install:
+  - travis_retry composer update ${COMPOSER_FLAGS} --prefer-dist --no-interaction --no-suggest
+
+script:
+  - vendor/bin/phpunit --coverage-text --coverage-clover=coverage.clover