Improved recovery (still experimental), new APIs and bugfixes.

* Added pythons bulk_read_by_id() API. Also while here point `bulk_read_by_name()` to `bulk_read()` for naming consistency.
* Fixed overwrite of old-format entry with new-format entry (ext format).
* Sorted gitignore and added *.py[co].
* Huge improvements to recovery script - now it's ready for integration tesing.