Allow crafting rope from twine

[Nix Halcyon]

Reason Why:  I have created several new worlds in the 1.20.3 release with the focus on sailing.  So I tweak the world generation settings to favor large oceans.  This has the side effect that I almost always spawn on a little island in the middle of the ocean that the game auto generates around coordinate 0,X,0.  This island seems to have rules that guarantee the presence of clay, wood, food, copper, fresh water ... just about everything you need to be able to survive and build a ship.  The only thing it does not guarantee is the presence of reeds/papyrus/vines.  Without these you cannot build rope.  No rope means no rafts, and no tongs for metal forging.  This prevents the creation of any form of water travel to escape the island.

I enjoyed the added challenge of having no way to expand my inventory.  I thought of it as a Castaway type scenario.  I was Robinson Crusoe trapped on an island, slowly rebuilding enough civilization to build a ship and sail to freedom.  It was great.  But then I started getting ready for smelting copper and realized I was stuck without rope to make tongs.

I think the most graceful solution is to allow the crafting of rope from twine, since this also makes logical sense, and should be a fairly easy tweak to the game.  The only time anyone would ever use it is if they are trapped on an island like I was because flax is a far more expensive resource than reeds are.  But Castaway is an interesting enough scenario that I think the change would greatly increase the fun of the game.