We had various overrides of the bootstrap defaults for font-size and line-height every time we made a pre tag,
and then some overrides of our overrides when we wanted something slightly different.
This moves the most basic overrides to apply to all pre tags,
reducing the number of downstream changes we need.
`pre`, `code` tags already set the font-family in these contexts.
Setting it again in the surrounding context is redundant,
and causes inconsistency when embedding notebooks in HTML
(e.g. nbviewer).
This was inspired by PR #4105.
* JavaScript output no longer requires calling container.show()
* Added output_javascript CSS class that has zero height when
empty.
* JavaScript error messages are properly indented with the prompt
area.
Jason Grout
Jonathan Frederic
MinRK
Brian E. Granger
Matthias BUSSONNIER