Use CBS subclasses to implement the fast-find and find-in-zones features. This avoids the need to control behaviour by passing Booleans, and it means that there is no wasted space in the CBS block structure when these features are not used.
Bring splay tree design up to date; add missing diagrams; move it to the "current" section of the manual.
Catch-up merge from master sources to branch/2014-03-30/addrset.