Added Travis CI config

Author: subins2000

.travis.yml

@@ -0,0 +1,35 @@
+matrix:
+  include:
+    # Linux
+    - os: linux
+      language: php
+      php: '5.6'
+
+    - os: linux
+      language: php
+      php: '7.0'
+
+    - os: linux
+      language: php
+      php: '7.1'
+
+    - os: linux
+      language: php
+      php: 'nightly'
+
+before_script:
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then brew update ; fi; # travis image is quite old, update to have latest dependecies available
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then brew tap homebrew/dupes ; fi;
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then brew tap homebrew/versions ; fi;
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then brew tap homebrew/homebrew-php ; fi;
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then brew install ${OSX_PHP_VERSION} ; fi; # install PHP
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then curl -sS https://getcomposer.org/installer | php ; fi; # install composer
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then mv composer.phar /usr/local/bin/composer | php ; fi; # install composer globally
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then export PATH="$(brew --prefix homebrew/php/${OSX_PHP_VERSION})/bin:$PATH" ; fi; # app php to path
+  - if [[ $TRAVIS_OS_NAME == 'osx' ]] ; then brew install coreutils ; fi; # truncate command:
+  - composer self-update
+  - composer require phpunit/phpunit:4.8.35 --prefer-dist --no-interaction --dev
+  - composer update
+
+script:
+  - vendor/bin/phpunit -c testing/phpunit.xml