Bootstrap 4 support

[coxrichuk]

This may not be the best place to ask .... but

With this announcement yesterday (twbs/bootstrap#20631) that support for bootstrap 3 will be coming to an end, are there any plans in place to move angular-ui over to bootstrap 4?

[wesleycho]

Closing, as we have already addressed this question in #4234. We don't have the bandwidth to work this in in this library, most of our efforts is focused on the ng2 version, which does support Bootstrap 4.