Use cornerstone cache to determine what is/is not loaded
Use cornerstone cache to determine what is/is not loaded

Should more accurately reflect reality, and also handle unloading images from the cache.

chafey/cornerstoneTools,leonardorame/cornerstoneTools,cornerstonejs/cornerstoneTools,cornerstonejs/cornerstoneTools,google/cornerstoneTools,leonardorame/cornerstoneTools,swederik/cornerstoneTools,google/cornerstoneTools,HorizonPlatform/cornerstoneTools,HorizonPlatform/cornerstoneTools,cornerstonejs/cornerstoneTools,swederik/cornerstoneTools