Add the ability to automatically stop the timer when the wave reaches a specific distance

[Panquesito7]

Hope the title's clear enough to describe the feature request. Thanks.

[brettfiedler]

Hi @Panquesito7, thanks for the issue! This sim is currently undergoing a republication to update it to work alongside other PhET maintenance processes, but is not seeing major design changes.

We'll keep this issue here for the team to revisit when this simulation is undergoing a future 2.0 update.