This is a breaking change. This commit separates syncstorage and tokenserver settings into separate structs that are contained by a parent `Settings` struct. This means that any env vars that hold settings specific to syncstorage (e.g. `SYNC_DATABASE_URL`) have been renamed to `SYNC_SYNCSTORAGE__DATABASE_URL`. Any settings that were moved from the top-level `Settings` struct to the lower level, syncstorage-specific struct will now have a `SYNC_SYNCSTORAGE__` prefix instead of a `SYNC_` prefix.
Closes#1276
* tag 0.8.1 for release and include scripts for setting up sentry releases
closes#910
* include details on sentry releases in changelog
* update changelog to include test fix
