Request: Update Tether dependency

[nurtext]

Could you please update Tether dependency to it's latest release?

[jeffling]

@nurtext Would you like to do this? Feel free to submit a PR. if the API has not changed, it should be as easy as just bumping the version on bower, updating your local deps, and running npm run dist

[nurtext]

@jeffling already did it, but I was on vacation. PR coming soon 😉