qualify interpretations to avoid clashes
more abstract naming
tuned order of arguments
del_max -> split_max
moved and renamed lemmas
more symbols;
isabelle update_cartouches -c;
prefer formal comments;
replaced raw proof blocks by local lemmas
introduced aggressive splitter "split!"
got rid of class cmp; added height-size proofs by Daniel Stuewe
tuned
added invariant proofs to AA trees
more canonical names
tuned layout
added AA_Map; tuned titles
added AA trees