Don't display drafting alerts when riders are parked by the roadside

This is mostly a cosmetic issue, but when your rider is parked by the roadside, it will receive constant “Close the Gap” alerts when other riders past closely. There’s no real reason to get those alerts as other riders pass, if you’re not actually moving. 

If the rider is traveling at 0mph or has a foot down (or however you determine a rider to be “Stopped”), the alerts shouldn’t be shown. The sound is similar to the disconnect warning and popup messages, so it can be distracting if you step away from the bike momentarily and hear them come bleeping in. 

To add to this, when I’m really cranking and passing people left and right, I don’t really want that ‘close the gap’ message coming up and then disappearing every few seconds. Maybe add in some logic so that if the rider in front of you is within ‘x’ percent of your current speed, then it displays the message? If I’m obviously going to close the gap and blow by somebody, I don’t really need the motivational support!