.travis.yml in zdm-1.0.7 vs .travis.yml in zdm-1.1.0

@@ -1,16 +1,15 @@
 language: ruby
 
 rvm:
-  - 2.3.0
-  - 2.4.0
+  - 2.4.3
+  - 2.5.1
 
 sudo: false
 
 gemfile:
-  - gemfiles/4.1.gemfile
   - gemfiles/4.2.gemfile
-  - gemfiles/5.0.gemfile
+  - gemfiles/5.2.gemfile
 
 services:
   - mysql
 before_install:
   - mysql -e 'CREATE DATABASE zdm_test DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;'