unify json-java gemspec with the baseline

ext/json/json.gemspec

@@ -4,13 +4,15 @@ Gem::Specification.new do |s|
   s.name = "json"
   s.version = "2.3.1"
 
-  s.required_rubygems_version = Gem::Requirement.new(">= 0") if s.respond_to? :required_rubygems_version=
-  s.require_paths = ["lib"]
-  s.authors = ["Florian Frank"]
+  s.summary = "JSON Implementation for Ruby"
   s.description = "This is a JSON implementation as a Ruby extension in C."
+  s.licenses = ["Ruby"]
+  s.authors = ["Florian Frank"]
   s.email = "flori@ping.de"
+
   s.extensions = ["ext/json/ext/generator/extconf.rb", "ext/json/ext/parser/extconf.rb", "ext/json/extconf.rb"]
   s.extra_rdoc_files = ["README.md"]
+  s.rdoc_options = ["--title", "JSON implemention for Ruby", "--main", "README.md"]
   s.files = [
     ".gitignore",
     ".travis.yml",
@@ -128,10 +130,8 @@ Gem::Specification.new do |s|
     'source_code_uri'   => 'https://github.com/flori/json',
     'wiki_uri'          => 'https://github.com/flori/json/wiki'
   }
-  s.licenses = ["Ruby"]
-  s.rdoc_options = ["--title", "JSON implemention for Ruby", "--main", "README.md"]
+
   s.required_ruby_version = Gem::Requirement.new(">= 2.0")
-  s.summary = "JSON Implementation for Ruby"
   s.test_files = ["tests/test_helper.rb"]
 
   s.add_development_dependency("rake", [">= 0"])