travis: add mariadb test

.travis.yml

@@ -1,3 +1,5 @@
+sudo: false
+
 language: perl
 perl:
    - "blead"
@@ -10,6 +12,18 @@ perl:
    - "5.8"
    - "5.6"
 
+matrix:
+    include:
+        - addons:
+             mariadb: 5.5
+          perl: 5.20
+        - addons:
+             mariadb: 10.0
+          perl: 5.20
+        - addons:
+             mariadb: 10.1
+          perl: 5.20
+
 before_install:
    - git clone git://github.com/haarg/perl-travis-helper
    - source perl-travis-helper/init