Switch FTBA to use https://api.feed-the-beast.com/v1 (#3174)

examples/ftba/compose.yml

@@ -0,0 +1,21 @@
+services:
+  mc:
+    image: itzg/minecraft-server
+    ports:
+      # expose the Minecraft server port outside of container
+      - "25565:25565"
+    environment:
+      # REQUIRED for all types
+      EULA: "TRUE"
+      # Set server type (vs the default of vanilla)
+      TYPE: FTBA
+      # Use Pack ID from https://www.feed-the-beast.com/modpacks/119-ftb-presents-direwolf20-120?tab=about
+      FTB_MODPACK_ID: "119"
+#      FTB_MODPACK_VERSION_ID: ""
+    volumes:
+      # use a named, managed volume for data volume
+      - data:/data
+
+volumes:
+  # declared the named volume, but use default/local storage engine
+  data: {}