Fixed #686 - "Disk Drive and Storage Disk issue in server environment."

src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/fluid/FluidStorageNBT.java

@@ -198,7 +198,7 @@ public abstract class FluidStorageNBT implements IFluidStorage {
         NBTTagCompound otherTag = new NBTTagCompound();
 
         otherTag.setInteger(NBT_STORED, getStoredFromNBT(tag));
-        otherTag.setTag(NBT_FLUIDS, new NBTTagList());
+        otherTag.setTag(NBT_FLUIDS, new NBTTagList()); // To circumvent not being able to insert disks in Disk Drives (see FluidStorageNBT#isValid(ItemStack)).
 
         return otherTag;
     }