title: Nokogiri installation fails -libxml2 is missing
body: <p>I always worked my way around Nokogiri installation issues by following the documentation in the "<a href="http://nokogiri.org/tutorials/installing_nokogiri.html" rel="noreferrer">Installing Nokogiri</a>" tutorial.</p>
  
  <p>But this time, even after installing all the dependencies, Nokogiri hasn't been installed.  I get the following error: </p>
  
  <pre><code>libxml2 is missing.  please visit &lt;http://nokogiri.org/tutorials/installing_nokogiri.html&gt;
  </code></pre>
  
  <p>I tried installing it by specifying the libxml2 and libxslt directories:</p>
  
  <pre><code>sudo gem install nokogiri -- --with-xml2-include=/usr/include/libxml2 --with-xml2-lib=/usr/lib --with-xslt-dir=/usr/
  </code></pre>
  
  <p>but it returned the same error.</p>
  
  <p>I followed all the other related Stack Overflow articles and none helped.  Does anyone have a solution?</p>