Generalize tooltip into popover control
Use the same popover control for tooltip as the preset browser and tools list popovers
Smartly position the preset browser popover and menu bar tooltips to stay fully onscreen
Position most tooltips closer to their controls
Fix small gap that could appear between a tooltip and its arrow
Allow wider toolbar tooltips
What could happen was:
- user could right click on a line
- this would trigger `disabled()` checks for each operation buttons
- the line was not fully downloaded, so would return `disabled()` 'not_downloaded'
(and also start download of the missing tiles)
- then the tooltip would pop into existence, calling `tooltip()`
- which calls `disabled()` again
- but this time it's fine and the `disabled()` is false
- so you'd see a greyed out button but the tooltip said everyting is ok and
you can click the button anyway
I fixed this by just caching the disabled test. This is probably ok anyway
because these tests can be expensive, and then the user will see a consistent
message like "The line is not yet fully downloaded".
If the user clicks off the line and back onto it, iD will reenter select mode,
rebuild the menu, redo the disabled test, and they will see the button enabled.
