Update supported Ruby and Rails versions

.travis.yml

@@ -10,8 +10,8 @@ env:
 
 rvm:
   - 2.5.1
-  - 2.4.2
-  - 2.3.5
+  - 2.4.4
+  - 2.3.7
   - 2.2.8
 
 gemfile:

Appraisals

@@ -72,7 +72,7 @@ end
 appraise '5.1' do
   instance_eval(&shared_dependencies)
 
-  gem 'rails', '~> 5.1.4'
+  gem 'rails', '~> 5.1.6'
   gem 'rails-controller-testing', '>= 1.0.1'
   gem 'puma', '~> 3.7'
   gem 'sass-rails', '~> 5.0'

NEWS.md

@@ -4,8 +4,8 @@ This release mainly brings the gem up to date with modern versions of Ruby and
 Rails and drops support for older, unsupported versions. The compatibility list
 is now:
 
-* **Ruby:** 2.4.2, 2.3.5, 2.2.8
-* **Rails:** 5.1.4, 5.0.6, 4.2.9
+* **Ruby:** 2.5.1, 2.4.4, 2.3.7, 2.2.8
+* **Rails:** 5.2.1, 5.1.6, 5.0.6, 4.2.9
 
 ### Backward-incompatible changes