title: WooCommerce stock per attribute
body: <p>I have a technical problem with the WooCommerce plugin that I can't seem to find an answer for.
  I got a variable product that has two different times for workshops. 
  So an example to simplify:</p>
  
  <p>Product: Event day ticket</p>
  
  <p>Workshop 1: Red | Blue | Green</p>
  
  <p>Workshop 2: Red | Blue | green</p>
  
  <p>On workshop 1, every attribute needs to have 5 stock but on workshop 2 every attribute needs to have 10 stock.</p>
  
  <p>I can make combination variables but if I do that, every combination has it's own stock. Not the attribute itself. </p>
  
  <p>Any idea on how to work with issue?</p>
  
  <p>I hope I explained it well enough.</p>