Why are we nullifying the iOS tap highlight?

Created by: cvrebert

I tend to agree with the commenter in https://github.com/twbs/bootstrap/commit/85db846b651842444d374f8e54f3f362ca18d08e#diff-ef2c30c269c7f0b514325e65587e24deR13 The tap highlight seems like a nice affordance. Why does Reboot kill it? CC: @mdo @patrickhlauke