参考 https://github.com/ipython-contrib/jupyter_contrib_nbextensions
安装：
pip install jupyter_contrib_nbextensions
或者
pip install https://github.com/ipython-contrib/jupyter_contrib_nbextensions/tarball/master
jupyter contrib nbextension install --user
#此处注意下
1 Finally, the --skip-running-check option flag is provided in order to allow the installation to proceed even if a notebook server appears to be currently running (by default, the install will not be performed if a notebook server appears to be running). 2 jupyter contrib nbextension install --user --skip-running-check
