feat: plugin methods center/zoom/overview-image
Closes MIN-229
Objective
Implement plugins methods for zoom/center/overview-image data access and manipulation
What has been done:
- getZoom
- setZoom
- getCenter
- setCenter
- getCurrentOverviewImage
- getOverviewImages
- hideOverviewImageModal
- selectOverviewImage
- showOverviewImageModal
- unit tests
- docs