merge revision(s) 40013,40032: [Backport #8188]

	* class.c (HAVE_METACLASS_P): should check FL_SINGLTON flag before get
	  instance variable to get rid of wrong warning about __attached__.
	  [ruby-core:53839] [Bug #8188]

	* class.c (HAVE_METACLASS_P): should check FL_SINGLETON flag before get


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@40294 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 40014: [Backport #8199]

	Document the default Net timeout values by @toolmantim [GH fixes #269]

 * lib/net/{ftp,http,pop,smtp}.rb: added documentation for default values.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@40295 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 40015: [Backport #8197]

	doumentation by @toolmantim [GH fixes #270]

 * timeout.rb: Document Timeout::timeout 0 and nil argument behavior



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@40296 b2dd03c8-39d4-4d8f-98ff-823fe69b080e