title: Travis is not uploading cache directory? Why?
body: <p>On this build, I have a cache directory in the settings, 
  where I install all dependencies, strangely travis does not execute <code>before_cache</code> and does not upload the cache?</p>
  
  <p>My repository uses the settings as explained for caching:
  <a href="https://i.stack.imgur.com/PdhPp.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PdhPp.png" alt="enter image description here"></a></p>
  
  <p><a href="https://travis-ci.org/gabyx/ApproxMVBB/jobs/256581132" rel="nofollow noreferrer">https://travis-ci.org/gabyx/ApproxMVBB/jobs/256581132</a></p>
  
  <p>Its strange that travis reports the following in the log</p>
  
  <pre><code>Setting up build cache
  $ export CASHER_DIR=$HOME/.casher
  0.14s$ Installing caching utilities
  0.00s
  0.61sattempting to download cache archive
  fetching master/cache-linux-precise-49ed8168a954ef68babd02034884f858ddc4fe3ca0368ba1270828dc239856eb--compiler-gpp.tgz
  fetching master/cache--compiler-gpp.tgz
  could not download cache
  0.00s
  0.45sadding /home/travis/ApproxMVBBCache to cache
  creating directory /home/travis/ApproxMVBBCache
  </code></pre>
  
  <p>Anybody has any idea?</p>