Far too slow on initial render of pages with > 100 tooltips

[kybishop]

This is even a problem with lazy rendering enabled. I believe the issue is that we aren't lazy enough. Will have to see about pushing lazy-rendering and visibility toggling down a layer into ember-popper.

It's quite possible a separate and/or custom impl of ember-popper is needed for tooltip libraries; ember-popper might already be too far down the road of supporting popovers alone for people to accept the burden of adding hide/show logic to the addon.

[kybishop]

The lazy-rendering of #102 is unfortunately not a11y friendly since information is hidden until a tooltip is rendered. I'll have to look more into a11y to see if there is a known solution to this for lazy rendering.

If there is no known solution for screen readers, I plan to implement a barebones tooltip component after #102 to have an a11y-friendly solution. The idea is to prioritize performance over all else, and not offer any options besides hideOn, showOn, and isVisible.