Fixed mysql error occuring when someone is bying while having already byed
Fixed bye swap looking for someone which has already byed, if it cannot swap directly with the first one found, it now tries to find a swap match with the first one opponent and himself to make the first one bye
Stop tournament does not show anymore if the tournament has already started
If a round is finished, option "End tournament" is now available
The button "next round" does not show up anymore if the current round is not finished
When setting a score, inputs have now a default value of 0
Fixed division by zero php notice