Run the system test on travis

Signed-off-by: Xheni Myrtaj <myrtajxheni@gmail.com>

Author: xh3n1

.travis.yml

@@ -73,6 +73,11 @@ script:
   echo "Running the integration tests";
   vendor/bin/phpunit tests/Integration/;
 
+- >
+  echo;
+  echo "Running the system tests";
+  vendor/bin/phpunit tests/System/;
+
 - >
   echo;
   echo "Running the static analysis";