cubicweb-seda #13853099 Rename description fields [validation pending]

There is a SEDA 2 tag named <Description> who is different from "description fields" used for anotation.

Rename description fields in "documentation".

prioritynormal
typeenhancement
done in0.4.0
load left0.000
closed by#3dceed49305c [ui] Fix some translations
patch[ui] Fix some translations [applied]