Allow setting Discount % to 0

This may seem counter-intuitive, but it'd be nice to be able to set the discount percent to 0. Use case: We have multiple sales currently running. They are grouped by the discount percentage. For example, we have a 10% off rule, a 20% off rule, a 25% off rule, etc. We want to run a discount on a select group of products using a promo code and we want the products to go back to their MSRP for the duration of this promo. Currently, we'll need to go into each of our rules, find the products that are part of our new promo, and remove them from the sales rule. To put thes products back on sale after the promo, we'll either need to create a new rule that starts when our promo code ends, or to keep our rule setup clean, we'll need to go back into each of the original rules and add back the products we removed. It'd be helpful if instead, we could simply setup a new rule that included the products in our promo, set the discount to 0, and set the start and end times equal to when our promotion is running. Then, during these times, it would remove the other sales on the product. When the "0% sale" ended, it would then revert back to the other rules we already had setup. This goes against the app's principle concerning active rules with overlapping periods, so there would also need to be someway to specify that we want our new rule to take precedence over existing rules. Thanks for the app as it is already. Been a big help. Would love to hear your thoughts on this additions.