commented null return from ABTC.Holder.update() to avoid future deletion
refactor LongBTreeTest to JUnit test, make fanfactor configurable and set it low for unit tests, and protect from garbage overload in certain tests
cleanup
make clear() throw UAE
add missing previous assignment
trust sorted-ness on single-leaf tree
r/m Nullable annotations
comments
fix upperBound
TODO
more cleanup
cleanup 3
refactor ML.clear
rename Stack to Path
comments + renames
cleanup 4