pdf printing using pagedjs

[phaustin]

• clone paged_trio
• install and run the nbconvert printit template
• clone the two themes that are used by pyman (sphinx_rtd_theme) and quantecon-example (pydata-sphinx-theme)
• build these two examples with local imports of the sphinx themes to see how the jinja2 templates are used to create the html
• write our own sphinx theme that uses the header information from the printit template instead, so that we add pagedjs headers and pagebreaks to the two manuals
• commit the new theme (called paged_html?) into its own github repository so it's pip installable.
• modify the single notebook example at https://github.com/phaustin/MyST-NB/tree/utf_issue/docs/examples/utf_bug so it uses the theme -- i.e. change this line to "paged_html" and change the environment.yml file to install the new theme in the pip section.
• Substitute the quiz2 notebook for the appdx1 notebook
• post readme and invite collaborators: consistent parameter passing for html and latex-generated pdf executablebooks/MyST-NB#201

[marasolen]

This is ready for an alpha release

[marasolen]

I think this can be checked off now