fixup "allow users to not choose a default proposal sort order"
fixup "allow users to not choose a default proposal sort order"

interestingly, formencode's validator baseclass does
set _to_python (and other methods) to None instead of
empty functions.

DanielNeugebauer/adhocracy,phihag/adhocracy,alkadis/vcv,alkadis/vcv,liqd/adhocracy,DanielNeugebauer/adhocracy,liqd/adhocracy,alkadis/vcv,DanielNeugebauer/adhocracy,liqd/adhocracy,liqd/adhocracy,DanielNeugebauer/adhocracy,phihag/adhocracy,phihag/adhocracy,phihag/adhocracy,alkadis/vcv,phihag/adhocracy,DanielNeugebauer/adhocracy,alkadis/vcv