Fix for #2856
- Toolbar gets reshown when cancelling edit node dialog
- No shadow displayed upon save in edit node dialog
The latter is actually a more general problem. Function `mergeOptions` in `util.js`
made an assumption as to the correct value of field `enabled`. It now takes the value
from `globalOptions`, if present.
* { manipulation: { editEdge: { editWithoutDrag: function } } } edits an edge without dragging.
* An example of editing network edges without dragging, enabling label creation / change
* generate individual css files; fixes#1969
* simplified css bundleing
* add new generated dist-css files
* use chart specific css files in the examples