All GUI compile errors fixed, switched to excludes over includes in gradle build and lots, LOTS of more fixes.

src/main/java/appeng/container/ContainerOpener.java

@@ -0,0 +1,43 @@
+package appeng.container;
+
+import appeng.core.AELog;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.entity.player.PlayerInventory;
+import net.minecraft.inventory.container.Container;
+import net.minecraft.inventory.container.ContainerType;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Allows opening containers generically.
+ */
+public final class ContainerOpener {
+
+    private ContainerOpener() {
+    }
+
+    private static final Map<ContainerType<? extends AEBaseContainer>, Opener<?>> registry = new HashMap<>();
+
+    public static <T extends AEBaseContainer> void addOpener(ContainerType<T> type, Opener<T> opener) {
+        registry.put(type, opener);
+    }
+
+    public static boolean openContainer(ContainerType<?> type, PlayerEntity player, ContainerLocator locator) {
+        Opener<?> opener = registry.get(type);
+        if (opener == null) {
+            AELog.warn("Trying to open container for unknown container type {}", type);
+            return false;
+        }
+
+        return opener.open(player, locator);
+    }
+
+    @FunctionalInterface
+    public interface Opener<T extends AEBaseContainer> {
+
+        boolean open(PlayerEntity player, ContainerLocator locator);
+
+    }
+
+}