Only use supported versions of Ruby and Rails

Author: Bart de Water

.travis.yml

@@ -3,23 +3,11 @@ script: bundle exec rake test
 sudo: false
 
 rvm:
-- "1.9"
-- "2.0"
-- "2.1"
-- "2.2.2"
+- 2.2
+- 2.3
+- 2.4
 
 gemfile:
-- Gemfile.activesupport32
-- Gemfile.activesupport40
-- Gemfile.activesupport41
 - Gemfile.activesupport42
 - Gemfile.activesupport50
-
-matrix:
-  exclude:
-    - rvm: "1.9"
-      gemfile: Gemfile.activesupport50
-    - rvm: "2.0"
-      gemfile: Gemfile.activesupport50
-    - rvm: "2.1"
-      gemfile: Gemfile.activesupport50
+- Gemfile.activesupport51

Gemfile.activesupport40

@@ -1,4 +1,4 @@
 source "https://rubygems.org"
 gemspec
 
-gem 'activesupport', '~> 3.2.0'
+gem 'activesupport', '~> 5.1.0'

Gemfile.activesupport41

@@ -14,7 +14,8 @@ Gem::Specification.new do |s|
 
   s.rubyforge_project = "active_utils"
 
-  s.add_dependency('activesupport', '>= 3.2', '< 5.2.0')
+  s.required_ruby_version = '>= 2.2'
+  s.add_dependency('activesupport', '>= 4.2', '< 5.2.0')
   s.add_dependency('i18n')
 
   s.add_development_dependency('rake')