Allow programmatic navigation of the viewport of the PdfViewer.

A remote go-to action is similar to an ordinary go-to action but jumps to a destination in another PDF file instead of the current file.

Support for horizontal scrolling the Pdf document in the viewer: 
Horizontal single page (go through the pages swiping/scrolling left and right)
Horizontal multi-page stacked (not possible, go through the pages swiping/scrolling left and right)

Provide support for lots of image formats when exporting PDF documents.

provide an option for FitPageToWidth. The current option is to fit document to width.

Implement API for adding document outline (a.k.a bookmarks).

When RadPdfViewer is used in a master-detail page, I should maintain the previous page index when I traverse between pages.

For example page loaded event: the purpose of the event to get a callback whenever a page is loaded and the page information is available.