fix #17043 - add Diet preset and link it in some others, add more cuisine=* values, deprecate cuisine=vegan|vegetarian in favor of diet:vegan|vegetarian (patch by naoliv) icon self created, derived from our farm icon, CC0 and PD licensed, improve the farm icon too
fix #17798 - add opening_hours:kitchen=*, deprecate kitchen_hours=* in favor of opening_hours:kitchen=*, add reservation=* to more presets