Remove bundler version requirement in gemspec files

Author: estolfo

elasticsearch-model/elasticsearch-model.gemspec

@@ -44,7 +44,7 @@ Gem::Specification.new do |s|
   s.add_dependency "activesupport",       '> 3'
   s.add_dependency "hashie"
 
-  s.add_development_dependency "bundler", "~> 1.3"
+  s.add_development_dependency "bundler"
   s.add_development_dependency "rake", "~> 11.1"
 
   s.add_development_dependency "elasticsearch-extensions"

elasticsearch-persistence/elasticsearch-persistence.gemspec

@@ -46,7 +46,7 @@ Gem::Specification.new do |s|
   s.add_dependency "activemodel",         '> 4'
   s.add_dependency "hashie"
 
-  s.add_development_dependency "bundler", "~> 1.5"
+  s.add_development_dependency "bundler"
   s.add_development_dependency "rake", "~> 11.1"
 
   s.add_development_dependency "oj" unless defined?(JRUBY_VERSION)

elasticsearch-rails/elasticsearch-rails.gemspec

@@ -40,7 +40,7 @@ Gem::Specification.new do |s|
 
   s.required_ruby_version = ">= 1.9.3"
 
-  s.add_development_dependency "bundler", "~> 1.3"
+  s.add_development_dependency "bundler"
   s.add_development_dependency "rake", "~> 11.1"
 
   s.add_development_dependency "elasticsearch-extensions"