Parameterize queries, clean layout, use BETWEEN.
Remove left-over debugging output.
REBASE with parameterize.
Include POSIX timestamp of recency.
Add uptime plotting log output; fix punctuation.
Use self-join for size estimate. Thanks Eleriseth!

This is faster than intersection, especially along with a covering
index.
Update todo.
Add new database version: fixes to indexes.

- Add covering index for size estimate.
- Remove unneeded indexes for identifier.
- Add missing time index for store size.
Update changelog.