Add popover/anchor positioning polyfills

[srambach]

Describe the enhancement
Add and test the anchor positioning/popover polyfills into our framework and validate that they implement what we need.

Any other information?
Popover polyfill from Oddbird
Anchor positioning polyfill from Oddbird

Follow-on: if successful, begin POCs for replacing popover, tooltip, and possibly other components currently using popper.

[dlabaj]

Polyfill was not working when tested. Can talk with @wise-king-sullyman if you have an questions on this.