Added rather ugly rapid performance test class.
Changed array_randitem to also return array index so that it can be used for fast removal.
Added verbose and non-verbose mode to the perf_test.
Got rid of mandatory p argument in skiplist, using default of 7 which seems to perform best (probably primes work in general best due to how we implement the random level choice?).
Moved to us per call as unit of testing instead, and added a way of listing known overheads.
Overhead handling fixes.
Clarified handling of non-busted based stress tests.
Added indexed set, which has mainly faster count + randitem methods (no other public API differences, but significantly more memory consumption). Oh well.
iset optimization.
Added total times to debug outputs too for perf_test.
Converted testware to use iset instead of array - it's the correct 'fast' way to deal with random test data anyway (~2x as slow create, but much faster insert+remove).
Added some more core thing speed tests.
Got rid of redundant get_first calls.
Added new 'n' parameter to perf_test, which can be used to indicate that the callback did something N times.
Stopping advertising of services if not owner of a link.