LPS-33763 and LPS-33765 Portlet export and import dialogs

Hey Nate,

These are the final commits for the story LPS-33635. We've just applied the same pattern and JS component as for the layout export/import dialogs. The only remarkable changes I'd like you to review are:

* To solve LPS-34690 we now check if a change link exists before binding the click event on it.
* We now pass the title of the content-option dialogs as a parameter of the JS component.

Thanks!

@JorgeFerrer
@LeventeHudak