Quick Scoreboard - Button functionality needs cleaned up

[EricSSartorius]

• [x] Currently, if the 'end' button is pushed before 'start', then the timer will automatically start at '0' no matter what the time. Need to hide the 'end' button unless the timer is going down.
• [x] After the timer reaches zero after counting down, it would be nice if it went back to the time it originally started at. not absolutely necessary but good for UX.
• [x] Add a reset button that puts the timer at the time originally started at and puts both scores at zero