more robust expose_proofs corresponding to register_proofs/consolidate_theory; expose_proofs of class algebra more aggresively, to ensure early export within original theory/session context;

reduce dependencies of Ordered_Euclidean_Space; move more general material from Cartesian_Euclidean_Space

reduce dependencies of Ordered_Euclidean_Space

Moved or deleted some out of place material, also eliminating obsolete naming conventions

expose derivations more thoroughly, notably for locale/class reasoning;

clarified errors;

determine proof boxes from exported proof (NB: thm_boxes is not sufficient due to OfClass proofs);

more operations;

tuned whitespace;

more robust;