Tested custom trees with the custom master fix in place — the original
still hangs. The tree incompatibility is a separate issue from the
SuperMaster path hang (both are real problems, both are now understood).
Custom trees give ~40% better compression for text data (1066 vs 1688
bytes for textfile.txt) but are incompatible with nuke1's assumptions.
Default tree retained for backward compatibility.
Updated roadmap to separate the backward compat (done) from the tree
optimization (remaining).
75a5ea541e