MAGN-5509 View.ExportAsImage only exports current view

This PR fixes Issue #3213. When updating this node to work with the file changes, by changing the ExportImageOptions ExportRange.VisibleRegionOfCurrentView, I inadvertently made this node always export the current view. I've added back the previous functionality which sets ExportRange to "SetOfViews", passing in the InternalView of our Element.View. I also re-added the logic that handles renaming the crazy file names that Revit produces with the name passed into the node.

One system test has been added to cover this functionality. Two units tests have been added to cover this functionality.

PTAL:
- [x] @Steell 

Merge:
- [ ] Revit2015