fix bug when orig_weight is measured without cup

How to reproduce:
 - place cup
 - pour first bottle
 - take cup away while first bottle is turning up
 - second bottle will measure orig_weight == 0 instead of cup weight
   because there is no cup
 - second bottle turns down until it notices cup is missing
 - bottle turns up and waits for cup
 - place cup
 - bottle pours to few because cup weight was measured wrong

Solution: there must be cup when measuring its weight.
add hardware abort btn