0.15.9

Features

• Add timeouts for tokenserver database calls. (#1561) (2584b977)
• Add metrics, gcp logging to tokenserver scripts (#1555) (6537783a)
• Add normalized ReportableError to errors (#1559) (77181308)

Bug Fixes

• nix-shell: update pkgconfig -> pkg-config build input (#1562) (a55e3738)
• Allow threadpool size to be set. (#1560) (ab7b4221)

Doc

• Remove commented code, unneeded TODO, unneeded collision tracking (#1563) (5cdfd034)