Add a DICOM-SR report viewer (popup) that is able to load SR instances associated with a series for review

OHIF's current handling of DICOM-SR reports can be confusing, particularly in places where there are multiple series that each might have one or two reports associated with them. A better solution is needed to review specific reports associated with a particular image (similar to how the annotations and segmentations currently work).

Desired goals:

1. Have an indicator associated with the image review screen that indicates if an SR instance exists for the currently active series.
2. When clicked, have a popup window load (similar to the tag viewer) which shows the name of the active series and a dropdown of report instances associated with it.
3. If the user clicks on the dropdown, it should show a list of other active reports.
4. If another report is clicked, the report viewer should change to that report.