update ruby install task to use libyaml + libffi

Rakefile

@@ -103,12 +103,18 @@ task "ruby:install", :version do |t, args|
   version = args[:version]
   name    = "ruby-#{version}"
   prefix  = "/app/vendor/#{name}"
+  usr_dir = "usr"
   Dir.mktmpdir("ruby-") do |tmpdir|
     Dir.chdir(tmpdir) do |dir|
       FileUtils.rm_rf("#{tmpdir}/*")
 
       sh "curl http://ftp.ruby-lang.org/pub/ruby/1.9/#{name}.tar.gz -s -o - | tar vzxf -"
-      sh "vulcan build -v -o #{name}.tgz --source #{name} --command=\"./configure --disable-install-doc --prefix #{prefix} && make && make install\""
+      FileUtils.mkdir_p("#{name}/#{usr_dir}")
+      Dir.chdir("#{name}/#{usr_dir}") do
+        sh "curl #{VENDOR_URL}/libyaml-0.1.4.tgz -s -o - | tar vzxf -"
+        sh "curl #{VENDOR_URL}/libffi-3.0.10.tgz -s -o - | tar vzxf -"
+      end
+      sh "vulcan build -v -o #{name}.tgz --source #{name} --command=\"mv usr /tmp && ./configure --disable-install-doc --prefix #{prefix} && env CPATH=/tmp/#{usr_dir}/include:\\$CPATH CPPATH=/tmp/#{usr_dir}/include:\\$CPPATH LIBRARY_PATH=/tmp/#{usr_dir}/lib:\\$LIBRARY_PATH make && make install\""
       s3_upload(tmpdir, name)
     end
   end