Bootstrap Rivencraft for NeoForge 1.21.1

NOTICE

@@ -0,0 +1,11 @@
+Rivencraft
+
+This project is a community-created port and spiritual successor to Mystcraft.
+It is not an official release of Mystcraft.
+
+Mystcraft Legacy source: https://github.com/Mystcraft/Mystcraft-Legacy
+Mystcraft Legacy copyright: XCompWiz and contributors
+Mystcraft Legacy license: GNU Lesser General Public License version 3
+
+The initial build layout is derived from the official NeoForge 1.21.1
+ModDevGradle MDK: https://github.com/NeoForgeMDKs/MDK-1.21.1-ModDevGradle