Update other dependencies.

Author: ioquatix

Gemfile

@@ -3,16 +3,15 @@ gemspec
 
 gem 'jruby-openssl',                                       :platforms => :jruby
 
-# compatibility restrictions for http clients under existing travis test environments
-gem 'public_suffix', '~> 2.0'   # or remove rubies < 2.1 from travis.yml
+gem 'public_suffix', '~> 4.0'
 
 # http clients
 gem 'httpclient',          '~> 2.3',    :require => false
 gem 'curb',                '~> 0.8',    :require => false, :platforms => :ruby
 gem 'em-http-request',                  :require => false, :platforms => [:ruby, :jruby]
 gem 'em-synchrony',                     :require => false, :platforms => [:ruby, :jruby]
 gem 'excon',               '~> 0.21',   :require => false, :platforms => [:ruby, :jruby]
-gem 'net-http-persistent', '~> 3.0',    :require => false
+gem 'net-http-persistent', '~> 4.0',    :require => false
 gem 'http',                             :require => false
 
 # adapter extensions

httpi.gemspec

@@ -11,7 +11,8 @@ Gem::Specification.new do |s|
   s.homepage    = "http://github.com/savonrb/#{s.name}"
   s.summary     = "Common interface for Ruby's HTTP libraries"
   s.description = s.summary
-  s.required_ruby_version = '>= 1.9.2'
+
+  s.required_ruby_version = '>= 2.3'
 
   s.license = 'MIT'