Enhance handling of transformations in VolumeBuilder

[tomlatham]

The VolumeBuilder helper class has a store for transformations and a function to populate it from the XML but that function is never called. In addition there is no access function (analogous to getShape or volume) to retrieve the transformations from the store. This PR adds a call to buildTransformations in the load function to populate the store and adds a new getTransform function to retrieve objects from the store.

BEGINRELEASENOTES

• Enhance handling of transformations in VolumeBuilder

ENDRELEASENOTES

[github-actions[bot]]

Test Results

   14 files     14 suites   7h 19m 22s :stopwatch:   363 tests   362 :white_check_mark: 0 :zzz: 1 :x: 2 496 runs  2 495 :white_check_mark: 0 :zzz: 1 :x:

For more details on these failures, see this check.

Results for commit 61d1653e.