adding Nettle Fibers

[Tarvian]

As you can only get twine from flax right now, nettle fibers could be a good addition to the game.

They could be encountered in summer and autumn at the edge of forests but not farmed (wont drop seeds) so you have an alternative if you dont want flax depleting your soil of Nitrogen.

but it requires more work:

• harvest nettles with a knife or scythe to get nettle stems
• rhetting of the stems
  • seal the stems (32 stems could be a good fit) in a barrel of water for 2 days (temperature irrelevant, never rots)
  • craft a "rhetting bundle" (maybe with 64 stems and 4 stones and one rope) and place it in a block of water for 3-7 days (needs to be over 10°C outside, rots after 7 days)
• dry stems for another 2 days
• combine the rhetted dried stems with a hammer to get fibers from them.