コマンド gem bundle install 'twitter-bootstrap-rails' を実行すると、結果は次のようになります。
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension
Gem files will remain installed in C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/therubyracer-0.10.1 for inspection.
Results logged to C:/RailsInstaller/Ruby1.9.3/lib/ruby/gems/1.9.1/gems/therubyracer-0.10.1/ext/v8/gem_make.out
An error occured while installing therubyracer (0.10.1), and Bundler cannot continue
誰が何が悪いのか教えてくれますか?