Work around issues with jupyterlab modules
Work around issues with jupyterlab modules

1. The codemirror module uses tildes to denote packages, but postcss does not recognize that, so we strip tildes.
2. Many packages use global variables in their CSS, so we import those definitions for each CSS file we compile.
jupyter-widgets/ipywidgets,ipython/ipywidgets,jupyter-widgets/ipywidgets,SylvainCorlay/ipywidgets,SylvainCorlay/ipywidgets,ipython/ipywidgets,SylvainCorlay/ipywidgets,ipython/ipywidgets,ipython/ipywidgets,SylvainCorlay/ipywidgets,jupyter-widgets/ipywidgets,jupyter-widgets/ipywidgets,ipython/ipywidgets