Add definition for jruby-1.6.4

share/ruby-build/jruby-1.6.4

+after_install_package() {
+  shim_jruby
+  remove_windows_files
+}
+
+shim_jruby() {
+  cd "${PREFIX_PATH}/bin"
+  sed -i "" 's/^#!\/bin\/bash/#!\/usr\/bin\/env bash/' jruby
+  ln -fs jruby ruby
+}
+
+remove_windows_files() {
+  cd "$PREFIX_PATH"
+  rm -f bin/*.exe bin/*.dll bin/*.bat bin/jruby.sh
+}
+
+install_package "jruby-1.6.4" "http://jruby.org.s3.amazonaws.com/downloads/1.6.4/jruby-bin-1.6.4.tar.gz" copy
+install_package "rubygems-1.6.2" "http://production.cf.rubygems.org/rubygems/rubygems-1.6.2.tgz" ruby