rbinstall.rb: gem subdirectories

* tool/rbinstall.rb (gem): prepare implies makedirs.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38871 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* doc/syntax/methods.rdoc:  Added Array Decomposition.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38872 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* properties.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38875 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
configure.in: clang temporary files

* configure.in: clang leaves temporary files when interrupted by
  SIGPIPE if input is not stdin.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38877 b2dd03c8-39d4-4d8f-98ff-823fe69b080e