added replace_cube method to model to update model with "complete" cube
objects that have more than just name and label.
first cut of load_cube_model to get "complete" cube object because cubes
now support dynamic models that can't offer complete cube objects up
front.
include non-calculated aggregation identifier in label in measure_info
missing this reference in load_cube_model
allow for absent aggregations property in measure_info
destroy hier._level_names, add Dimension.hierarchy()
use fakey model properly
fixed dimension resolution during Cube.parse
category for cube grabbed from desc