Loosen Rails version restriction

Allow Rails 5.1 applications to use JBuilder.

Author: maclover7

jbuilder.gemspec

@@ -9,7 +9,7 @@ Gem::Specification.new do |s|
 
   s.required_ruby_version = '>= 1.9.3'
 
-  s.add_dependency 'activesupport', '>= 3.0.0', '< 5.1'
+  s.add_dependency 'activesupport', '>= 3.0.0', '< 5.2'
   s.add_dependency 'multi_json',    '~> 1.2'
 
   s.files         = `git ls-files`.split("\n")