Store kernelspecs under jupyter, not IPython
Add kernel directory relative to sys.prefix
Default to systemwide installation for kernelspecs
Update kernelspec command line interface
Update kernelspec tests
add ability to unregister a preset

fix #7218
Revert change to test skip condition

This was part of a commit cherry picked from another branch, and this
change didn't make sense on this branch.
Move terminal less into better location
Make terminal pretty
invoke css
Style notebook as a document
no shadow on print media

Also hide celltoolbars
Address review comments
invoke css
Make things consistent
Prevent terminal from scrolling
invoke css
Additional aesthetic clean-up
invoke css
Improve edit app