Implement teleport in slideover

[indykoning]

This PR changes the global slideover to use the Teleport component so plain html can be passed without trouble

[royduin]

You're happy with the result? Should we have some docs on this? What's the simplest example how to use it?

[indykoning]

Yes, i'm quite content with the result. With no workarounds being necessary to properly render the html!
A simple example is already provided at the top of the global slideover component: https://github.com/rapidez/core/blob/master/resources/views/components/slideover/global.blade.php

We could add docs, though we do not currently do that for other components