cubicweb-file #2940243 drop the "shadow" argumement of the 'IImageAdapter.thumbnail' method [validation pending]

Shadowing is a matter of CSS

prioritynormal
typeenhancement
done in1.15.0
load1.000
load left0.000
closed by#4490014b941c [entities,uilib] kill computed drop-shadow support
patch[entities,uilib] kill computed drop-shadow support [applied]