implement Outliner.js and outlineCells.js
remove old cm_highlighted css class layout in celements2.css
add removeOutlinesForElement to Outliner
reimplement contextmenu-hover with outliner
change outline-width to 2 and make it configurable
add Outliner.js and outlineCells.js to loadBackend
fix removeOutliensForElement
add outlineElementAddClass
fix addFocus and removeFocus for elements with generated ids
add debugging output to contextmenu-hover.js
fix stability in behavior of contextmenu-hover.js
Merge branch 'dev' into feature-outlineCells
replace tabs by spaces
show / hide outlines on context menu open / close
Merge branch 'dev' into feature-outlineCells