eliminating confusion of psiTurk versus Experiment server.

Now the process that serves the experiment code is called the Experiment Server.  The process that serves dashboard is called the Dashboard Server.  I believe that experiment_server_controller.py and experiment_server.py could be combined.
Bumping up libraries to latest versions
Refactored image and page prefetching; folded showPage into PsiTurk object.
Fix for issue #32, Popen takes a flag to close file descriptors, which closes the port socket descriptor.
After name changes, server no longer booted, fixed here.
Merge branch 'dev' of https://github.com/NYUCCL/psiTurk into logging

* 'dev' of https://github.com/NYUCCL/psiTurk:
  After name changes, server no longer booted, fixed here.
  Fix for issue #32, Popen takes a flag to close file descriptors, which closes the port socket descriptor.
  Refactored image and page prefetching; folded showPage into PsiTurk object.
  Bumping up libraries to latest versions
  eliminating confusion of psiTurk versus Experiment server.
fixed typos that were crashing the experiment server
added yellow indicator lights for server on/off switch and some general refactoring
console theme for logger view
sidebar now launches logger with required assets
updated restart instructions