* remove benchmarks - not used for now, will need to be rewritten
* move some CLI settings to a separate struct
* move config saving to a shared function
* simplify zoom level CLI parsing
* rename main.rs to be the same name as generated binary (we can have
multiple bins later)
Partial fix of #1002
* [x] Move all summary code from `mbtiles/src/mbtiles.rs` to
`mbtiles/src/summary.rs`
* [x] Move Metadata and Validation function to separate files
* [x] Remove `filename` String from the summary stats - not much point
because it is accessible from the mbtiles struct itself
---------
Co-authored-by: Yuri Astrakhan <YuriAstrakhan@gmail.com>
After some thinking, it seems `mbtiles summary` (aliased as `mbtiles
info`) would be a bit better than stats. I renamed and adjusted
documentation, consolidating it in one doc page.
Other changes:
* use file system's file size, reporting 'unknown' if needed
* report page count
* moved bbox computation into a separate function
* inlined a number of things for readability
