clean-up
use codemirror gutter
use private namespace
use gutter to display breakpoints
extensions to display new, executed or dirty cell
toggle linenumbers for all cells
use private namespace
rename extension
move collect() to common file
add printview_button and cellstate extensions
add wiki images
add further images for wiki
update description to mention Wiki
add wiki images
Reorganize repository
Reorganize repository
Link to wiki
Correct link
Update codefolding wiki graphics
Update Codefolding