added helper functions for mapping SpatialIndex::Point to G4ThreeVector etc
added functions to get upper and lower bounds of region
added member variables to hold current bounding box of selected region
using SpatialIndex methods to store region bounding box
abort nearest neighbor computation if we are not outside of the previously loaded region
Added visitor as member variable
propgating result of parameterision update to stepping action
removed LRU caching operations from the parameterisation as it is the parameterisation we wish to cache
adding Cache as a member of the detector construction
removed LRUCache depandance, Cache is now a template
deriving from CacheBase (previously Cache) so we don't need the template paramters, and we can override the pull/push/pop methods
deleting index and cache on deconstruction
overriding CacheBase::pull to find nearest key within threshold
abstracted function to get nearest key
test for distance to each key and return the nearest with the threshold, otherwise return the arg key
added copy constructor, split ComputeNeighbors method given extra method testing if position outside of the currently loaded region
read from cache if we are outside of the currently loaded region, and if there is a chaced region that is near to the current position
Update the parameterisation before each event given the current position of the particle gun