Test php 7.3

Author: csandanov

Diff for: .travis.yml

@@ -5,8 +5,10 @@ services:
 
 env:
   matrix:
+    - DRUPAL_VER=8 PHP_VER=7.3
     - DRUPAL_VER=8 PHP_VER=7.2
     - DRUPAL_VER=8 PHP_VER=7.1
+    - DRUPAL_VER=7 PHP_VER=7.3
     - DRUPAL_VER=7 PHP_VER=7.2
     - DRUPAL_VER=7 PHP_VER=7.1
     - DRUPAL_VER=7 PHP_VER=5.6 GITHUB_RELEASE=1