ve.ce.Node: Emphasise slug transition with increasing outline offset

The outline is outside the boundary of the box model and as such doesn't
affect the page flow (cheap transition on a separate layer).

Re-ordered some of the rules as it wasn't working otherwise due
to cascading weight.

Change-Id: I42717be02360a45890539062c587c46141ad61df
Merge "ve.ce.Node: Emphasise slug transition with increasing outline offset"