RFC for 3.x

[sedghi]

Since Cornerstone3D 2.0 introduced significant changes with extensive migration guides, we chose to limit the scope of required modifications. Here's the list of changes - please share your preferences for version 3.0.

• Move all viewports change set event to VIEWPORT_NEW_IMAGE_SET
• Remove the edge for the viewports that are reported over and over here , here
• rename the metadata and providers in Cornerstone to dcmjs style naming, so instead of sopInstanceUID we use SOPInstanceUID