Use default Travis MySQL version

Nicolas Rodriguez · Nicolas Rodriguez · commit de461992b255 · 2017-05-13T01:50:18.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -17,7 +17,6 @@ services:
   - mysql
 addons:
   postgresql: '9.6'
-  mariadb: '10.0'
 before_script:
   - mysql -e 'create database ajax_datatables_rails;'
   - psql -c 'create database ajax_datatables_rails;' -U postgres
