GTCEu-Rubber-Multifarm

Registers GregTech CEu rubber tree saplings as a valid germling for the Forestry arboreal (tree) multifarm, enabling full automation:

• Planting — the multifarm plants rubber saplings on dirt/humus soil
• Harvesting — grown rubber trees are chopped automatically (logs + leaves)
• Sticky Resin — drops from natural rubber logs are collected by the farm
• Replanting — saplings from decayed leaves are picked up and reused