title: Travis-ci build fails with rake aborted! LoadError: cannot load such file -- rspec/core/rake_task
body: <p>I'm trying to add travis-ci to my project and it keeps failing with </p>
  
  <pre><code>rake aborted! 
  LoadError: cannot load such file -- rspec/core/rake_task
  </code></pre>
  
  <p>I'm currently using rspec 3.1</p>
  
  <p>Any ideas as to why this is failing and how to fix it?</p>
  
  <p>Here's my project that's failing:
  <a href="https://github.com/toymachiner62/readable_date_ranges/tree/tests" rel="nofollow">https://github.com/toymachiner62/readable_date_ranges/tree/tests</a></p>
  
  <p>EDIT</p>
  
  <pre><code>Using worker: worker-linux-9-2.bb.travis-ci.org:travis-linux-4
  system_info
  Build system information
  Build language: ruby
  git.checkout
  0.62s$ git clone --depth=50 --branch=master git://github.com/toymachiner62/readable_date_ranges.git toymachiner62/readable_date_ranges
  Cloning into 'toymachiner62/readable_date_ranges'...
  remote: Counting objects: 77, done.
  remote: Compressing objects: 100% (44/44), done.
  remote: Total 77 (delta 28), reused 71 (delta 26)
  Receiving objects: 100% (77/77), 13.73 KiB | 0 bytes/s, done.
  Resolving deltas: 100% (28/28), done.
  Checking connectivity... done.
  $ cd toymachiner62/readable_date_ranges
  $ git checkout -qf e78f9f7f350c2cfbb2ffb7751024a1bbb6ed732f
  rvm
  0.36s$ rvm use 1.9.3 --install --binary --fuzzy
  Using /home/travis/.rvm/gems/ruby-1.9.3-p550
  $ ruby --version
  ruby 1.9.3p550 (2014-10-27 revision 48165) [x86_64-linux]
  $ rvm --version
  rvm 1.26.0 (master) by Wayne E. Seguin &lt;wayneeseguin@gmail.com&gt;, Michal Papis &lt;mpapis@gmail.com&gt; [https://rvm.io/]
  $ bundle --version
  Bundler version 1.7.4
  $ gem --version
  2.4.2
  0.82s$ rake
  rake aborted!
  LoadError: cannot load such file -- rspec/core/rake_task
  /home/travis/build/toymachiner62/readable_date_ranges/Rakefile:2:in `&lt;top (required)&gt;'
  /home/travis/.rvm/gems/ruby-1.9.3-p550/bin/ruby_executable_hooks:15:in `eval'
  /home/travis/.rvm/gems/ruby-1.9.3-p550/bin/ruby_executable_hooks:15:in `&lt;main&gt;'
  (See full trace by running task with --trace)
  The command "rake" exited with 1.
  Done. Your build exited with 1.
  </code></pre>