Fix #10324: Add opt-in note to tooltip docs

[juthilo]

• Re-added a note (now callout) about need to opt in to tooltip docs
• Converted same note in popover section to callout

/to @cvrebert @mdo for review.

Fixes #10324.

[cvrebert]

I don't think the selector option is directly related to this?

[juthilo]

Oh, I just copied the existing thing from the popover section. But is that not how it works? You just call tooltip with no options on a jQuery selector you choose?

[cvrebert]

Erm, let me correct myself and clarify. The selector option is merely not the only way to do the manual initialization, depending on one's circumstances.

[juthilo]

Ah, okay. I'm clearly undereducated here, but I'll happily patch in any text suggestions.

[juthilo]

Could I get some more feedback on this? Don't really know what the text should be anymore... 😃

[cvrebert]

Maybe we should just go with the v2.3.2 phrasing?:

For performance reasons, the tooltip and popover data-apis are opt in, meaning you must initialize them yourself.

[juthilo]

Cool, done! Ping @mdo to confirm new phrasing.

[mdo]