Add onTouchTap to README

[ezralalonde]

There is no reference to onTouchTap in the project's README.

[leMaik]

Merged your last PR first, could you please rebase this? 😄

[ezralalonde]

Should be good to go now?

Thanks so much for sharing material-ui-chip-input. It's awesome! I also appreciate the quick response, and kind tone. I owe you a beer or something if you're ever in Saskatoon.

Cheers,
Ezra.

[leMaik]

@ezralalonde You are welcome! :) Saskatoon is a 14 h flight away from here, and as a german I'm not sure if a canadian beer is worth it. 😅 Thanks for the offer, though! 🍻