fix js to env to use new installation mechanism
fix js to env to use new installation mechanism

original-commit-id: e234d57ab5d07d9146a55c44a9e1607dc13d5791
original-commit-url: https://github.com/ipython-contrib/IPython-notebook-extensions/commit/e234d57ab5d07d9146a55c44a9e1607dc13d5791

jcb91/jupyter_nbextensions_configurator,jcb91/jupyter_nbextensions_configurator,jcb91/jupyter_nbextensions_configurator,jcb91/jupyter_nbextensions_configurator