Pass a target to toggle directive toggle and open methods

[wnvko]

Is your feature request related to a problem? Please describe.

I have a button. On mouseover I want to show a dropdown connected to the button.

Describe the solution you'd like

I expect toggle and open methods of dropdown to accept target as HTMLElement.

Describe alternatives you've considered

I can provide now OverlaySettings and show the dropdown correctly. However, I need to provide target and position strategy. As dropdown has its own default position strategy, I actually have to override it with the same one.