Add the option to add burned calories only to certain meals

This would allow me to set the calorie distribution at dinner to 0, so that I could only eat burned calories in the evening

So, if I've met my calorie goal in the morning and at lunch, but have spontaneously exercised a lot throughout the day, the calories are added to selected meals. This way, I could earn myself snacks and/or a larger dinner, and wouldn't be 200 calories short in the morning.