* lib/rubygems: Update to RubyGems 2.4.1 master(713ab65)

Complete history at:
  https://github.com/rubygems/rubygems/blob/master/History.txt#L3-L216
* test/rubygems:  ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47582 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/resolver/activation_request.rb

@@ -38,6 +38,13 @@ class Gem::Resolver::ActivationRequest
     end
   end
 
+  ##
+  # Is this activation request for a development dependency?
+
+  def development?
+    @request.development?
+  end
+
   ##
   # Downloads a gem at +path+ and returns the file path.