"Creative item pick" for blocks & plants

Issue description

It would be nice to have an option to select what item gets added to your creative inventory when clicking on a block with the "pick item" button. Would be useful for technical blocks and plants with multiple growth stages.
The required code is:
 

@Override
		public ItemStack getPickBlock(IBlockState state, RayTraceResult target, World world, BlockPos pos, EntityPlayer player) {
			return new ItemStack(ITEM);
		}

 

Issue comments

Yes, I have had some things I wished I had this option for. Custom crops are a pain to set up but creative mode always selects the same block state for the crop you right-click on. This would be great for selecting seeds like in vanilla Minecraft for people in creative.