Document how to use :container="false" to use the parent container automatically.

[orrd]

From reading the code, I learned that it's possible to have the Popover use the component's own parent as the "container" by setting the container to false with :container="false". I was glad to discover that because that was what I needed to make my code work.

Shouldn't that be in the documentation?

[Knogobert]

Thank you!!

[senatwj]

I was having an issue with y-axis placement being incorrect after scrolling down the page because of container elements being absolute positioned. Using this method to set a different container :container="getContainer" and
computed() { ..., getContainer() { return document.querySelector('.container-selector') } }
has appeared to fix this.

[Akryum]

Closed in #478