Links Awakening: Implement New Game (#1334)

Adds Link's Awakening: DX. Fully imports and forks LADXR, with permission - https://github.com/daid/LADXR

worlds/ladx/LADXR/locations/seashell.py

@@ -0,0 +1,14 @@
+from .droppedKey import DroppedKey
+from .items import *
+
+
+class Seashell(DroppedKey):
+    # Thanks to patches, a seashell is just a dropped key as far as the randomizer is concerned.
+
+    def configure(self, options):
+        if not options.seashells:
+            self.OPTIONS = [SEASHELL]
+
+
+class SeashellMansion(DroppedKey):
+    pass