Move more responsibility into `popoutElement` `popoutElement` now handles conditional modification of the passed step's element in general, as opposed to the more specialized handling of a `tour.modal == true` condition.
Move more responsibility into `popoutElement`
`popoutElement` now handles conditional modification of the passed step's element in general,
as opposed to the more specialized handling of a `tour.modal == true` condition.

Both `step.options.highlightClass` and `step.options.copyStyles` are now detected and handled
whenever they are present on the step, independent of the state of `tour.modal`.

`step.options.highlightClass` is applied before `step.options.copyStyles` causes `createHighlightOverlay`,
meaning the cloned element created by `createHighlightOverlay` will inherit the `highlightClass`.

shipshapecode/ember-shepherd,rwwagner90/ember-shepherd,rwwagner90/ember-shepherd,shipshapecode/ember-shepherd