title: I have still rake/rdoctask deprecated warning
body: <p>I've made bundle update a now I have still rake/rdoctask deprecated warning after running rake command.</p>
  
  <pre><code>WARNING: 'require 'rake/rdoctask'' is deprecated.  Please use 'require 'rdoc/task' (in RDoc 2.4.2+)' instead.
      at /home/cheetah/.rvm/gems/ruby-1.8.7-p302@tobiska/gems/rake-0.9.2.2/lib/rake/rdoctask.rb
  </code></pre>
  
  <p>I tried to read this tip <a href="http://matthew.mceachen.us/blog/howto-fix-rake-rdoctask-is-deprecated-use-rdoc-task-instead-1169.html" rel="noreferrer">http://matthew.mceachen.us/blog/howto-fix-rake-rdoctask-is-deprecated-use-rdoc-task-instead-1169.html</a> but my Rakefile is OK.</p>
  
  <p>I have no idea, how to solve this problem. Any tips? Thanks a lot.</p>
  
  <p>Martin</p>