Make unload of computers only suspend devices, only unload in destroy.

Avoids persisted data getting killed when it shouldn't.

src/main/java/li/cil/oc2/common/block/entity/ComputerTileEntity.java

@@ -271,6 +271,15 @@ public final class ComputerTileEntity extends AbstractTileEntity implements ITic
         }
     }
 
+    @Override
+    public void remove() {
+        super.remove();
+
+        // Regular dispose only suspends, but we want to do a full unload when we get
+        // destroyed, so stuff inside us can delete out-of-nbt persisted data.
+        virtualMachine.vmAdapter.unload();
+    }
+
     @Override
     public CompoundNBT getUpdateTag() {
         final CompoundNBT result = super.getUpdateTag();
@@ -381,7 +390,9 @@ public final class ComputerTileEntity extends AbstractTileEntity implements ITic
 
         ServerScheduler.removeOnUnload(getWorld(), onWorldUnloaded);
 
-        stopRunnerAndResetVM();
+        joinVirtualMachine();
+        virtualMachine.vmAdapter.suspend();
+
         busController.dispose();
         busElement.dispose();
     }

src/main/java/li/cil/oc2/common/vm/VirtualMachineDeviceBusAdapter.java

@@ -69,6 +69,10 @@ public final class VirtualMachineDeviceBusAdapter {
     public void unload() {
         fireLifecycleEvent(VMDeviceLifecycleEventType.UNLOAD);
 
+        suspend();
+    }
+
+    public void suspend() {
         deviceContexts.forEach((device, context) -> {
             if (context != null) {
                 context.invalidate();