Update testing matrix for new Rubys and Rails

Author: robzolkos

.travis.yml

@@ -5,50 +5,33 @@ cache:
   bundler: true
 
 before_install:
-  - gem install bundler
+  - gem uninstall -v '>= 2' -i $(rvm gemdir)@global -ax bundler || true
+  - gem install bundler -v '<2'
 
 rvm:
-  - 1.9.3
-  - 2.0.0
-  - 2.1.9
-  - 2.2.6
-  - 2.3.3
-  - 2.4.0
+  - 2.4.6
+  - 2.5.5
+  - 2.6.3
 
 gemfile:
   - Gemfile
-  - gemfiles/Gemfile-4-0-stable
-  - gemfiles/Gemfile-4-1-stable
   - gemfiles/Gemfile-4-2-stable
   - gemfiles/Gemfile-5-0-stable
+  - gemfiles/Gemfile-5-1-stable
+  - gemfiles/Gemfile-5-2-stable
+  - gemfiles/Gemfile-6-0-stable
   - gemfiles/Gemfile-edge
 
 matrix:
   allow_failures:
     - gemfile: gemfiles/Gemfile-edge
   exclude:
-    - rvm: 1.9.3
-      gemfile: Gemfile
-    - rvm: 2.0.0
-      gemfile: Gemfile
-    - rvm: 2.1.9
-      gemfile: Gemfile
-    - rvm: 1.9.3
-      gemfile: gemfiles/Gemfile-5-0-stable
-    - rvm: 2.0.0
-      gemfile: gemfiles/Gemfile-5-0-stable
-    - rvm: 2.1.9
-      gemfile: gemfiles/Gemfile-5-0-stable
-    - rvm: 1.9.3
+    - rvm: 2.4.6
+      gemfile: gemfiles/Gemfile-6-0-stable
+    - rvm: 2.4.6
       gemfile: gemfiles/Gemfile-edge
-    - rvm: 2.0.0
-      gemfile: gemfiles/Gemfile-edge
-    - rvm: 2.1.9
-      gemfile: gemfiles/Gemfile-edge
-    - rvm: 2.4.0
-      gemfile: gemfiles/Gemfile-4-0-stable
-    - rvm: 2.4.0
-      gemfile: gemfiles/Gemfile-4-1-stable
+    - rvm: 2.6.3
+      gemfile: gemfiles/Gemfile-4-2-stable
 
 notifications:
   email: false

gemfiles/Gemfile-4-0-stable

@@ -0,0 +1,5 @@
+source "https://rubygems.org"
+
+gemspec path: ".."
+
+gem "rails", github: "rails/rails", branch: "5-1-stable"

gemfiles/Gemfile-4-1-stable

@@ -0,0 +1,5 @@
+source "https://rubygems.org"
+
+gemspec path: ".."
+
+gem "rails", github: "rails/rails", branch: "5-2-stable"

gemfiles/Gemfile-5-1-stable

@@ -0,0 +1,5 @@
+source "https://rubygems.org"
+
+gemspec path: ".."
+
+gem "rails", github: "rails/rails", branch: "6-0-stable"