Preclinical Small Animal Imaging Acquisition Context

Adds support for storage of information related to acquisition of small animal images during preclinical research. This includes defining use cases and adding templates.

The Acquisition Context SR instances, a "description of the conditions present during data acquisition", will usually be in the same Study as the acquired images.

This supplement defines a new DICOM SR root template and supporting templates, as well as an IOD and SOP Class specific to that template to facilitate interoperability.