title: check if file exists on remote host with ssh
body: <p>I would like to check if a certain file exists on the remote host.
  I tried this:</p>
  
  <pre><code>$ if [ ssh user@localhost -p 19999 -e /home/user/Dropbox/path/Research_and_Development/Puffer_and_Traps/Repeaters_Network/UBC_LOGS/log1349544129.tar.bz2 ] then echo "okidoke"; else "not okay!" fi
  -sh: syntax error: unexpected "else" (expecting "then") 
  </code></pre>