title: can't install gem 'twitter-bootstrap-rails'
body: <p>When trying to bundle install get error. I get the same error with empty project.</p>
  
  <pre><code> Installing libv8 (3.3.10.4) with native extensions
     Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.
  
      C:/Ruby192/bin/ruby.exe extconf.rb
      *** extconf.rb failed ***
      Could not create Makefile due to some reason, probably lack of
     necessary libraries and/or headers.  Check the mkmf.log file for more
         details.  You may need configuration options.
  
    Provided configuration options:
      --with-opt-dir
      --without-opt-dir
      --with-opt-include
      --without-opt-include=${opt-dir}/include
      --with-opt-lib
      --without-opt-lib=${opt-dir}/lib
      --with-make-prog
      --without-make-prog
      --srcdir=.
      --curdir
      --ruby=C:/Ruby192/bin/ruby
      Checking for Python...Unable to build libv8: Python not found!
  
  
      Gem files will remain installed in C:/Ruby192/lib/ruby/gems/1.9.1/gems/libv8-3.3
   .10.4 for inspection.
     Results logged to C:/Ruby192/lib/ruby/gems/1.9.1/gems/libv8-3.3.10.4/ext/libv8/g
    em_make.out
     An error occured while installing libv8 (3.3.10.4), and Bundler cannot continue.
  
      Make sure that `gem install libv8 -v '3.3.10.4'` succeeds before bundling.
  </code></pre>
  
  <p>Here is my Gemfile:
         source 'https://rubygems.org'</p>
  
  <pre><code>  gem 'rails', '3.2.2'
    gem 'bootstrap-sass', '2.0.0'
    # Bundle edge Rails instead:
    # gem 'rails', :git =&gt; 'git://github.com/rails/rails.git'
     gem'devise'
  
    gem 'mysql2'
  
  group :deployment do
   gem 'pg'
  end
  </code></pre>
  
  <p>gem 'activemerchant'</p>
  
  <pre><code>Gems used only for assets and not required
  </code></pre>
  
  <p>in production environments by default.
     group :assets do
    gem 'twitter-bootstrap-rails'
      gem 'sass-rails',   '~> 3.2.3'
     gem 'coffee-rails', '~> 3.2.1'</p>
  
  <pre><code># See https://github.com/sstephenson/execjs#readme for more supported runtimes
  </code></pre>
  
  <p># gem 'therubyracer'</p>
  
  <pre><code> gem 'uglifier', '&gt;= 1.0.3'
  end
  
    gem 'jquery-rails'
  </code></pre>