Rule change: close "Recycle Unit" loop hole.
The action "Help Wonder" prevents the player from doing it in a city that
has enough shields to finish its current production. This protects against
a cheating player avoiding rules about what items can receive help from it
by receiving the help for a (finished) legal item and then build an item
that can't receive help from "Help Wonder". Give the action "Recycle Unit"
the same protection. This makes it consistent with "Help Wonder".
See hrm Feature #644056
git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@35104 a0f10bec-cc02-0410-94fc-a9cfff90b4cd