Merge pull request#37 from postgrespro/PBCKP-544-linkPBCKP-544 remove crc32c source patch for windows

Merge pull request#36 from postgrespro/PBCKP-564[PBCKP-564] Don't spam with "skip empty file" message

[PBKP-531] hotfix (#33)[PBKP-531] hotfixPGPROEE11 now supports ptrack for CFS---------Co-authored-by: Daniel Shelepanov <d.shelepanov@postgrespro.ru>

Version upgrade to 2.4

[PGPRO-5691] move mmapped ptrack map into shared postgres memory (#19)

Release 2.2.0TL;DR Since version 2.2 we use a different algorithm for tracking changed pages. Thus, data recorded in the `ptrack.map` using pre 2.2 versions of `ptrack` is incompatible with newer versions. After extension upgrade and server restart old `ptrack.map` will be discarded with `WARNING` and initialized from the scratch.* `ptrack` now uses two slots to record page change information. It  helps significantly reduce number of false positives with the same  `ptrack.map_size`. See#5 for details. Many thanks to@funny-falcon for  ideas, theory and review!* `ptrack_get_pagemapset()` now also displays a number of changed blocks  per file.* Added `ptrack_get_change_stat(start_lsn pg_lsn)` that can desplay statistic  of changes (number of files, pages and size in MB) since specified `start_lsn`.

Release 2.1.2* Fix int32 overflow when doing a `ptrack` checkpoint with  `ptrack.map_size` > 16 GB.* Adjust `ptrack` checkpoint buffer for a ~20% better performance.

Release 2.1.1* PostgreSQL 11 and 13 support. Thanks to@alubennikova.* Fixed an int32 overflow issue, when one was unable to setptrack.map_size to 2 GB and above. New limit is 32 GB.

Release 2.1.0Both `ptrack` engine and public SQL API are now inside extension. Onlycertain required hooks have been left as a PostgreSQL core patch.Also many things have changed since 2.0.0:* Fixed many compatibility bugs: alignment issues with atomics usage on Win32,  with atomics simulation via spinlocks.* Added versioning into the `ptrack` map.* Added automated standalone testing with `pg_probackup` via travis-ci in  different modes, including a 'legacy' mode, i.e. with `EXEC_BACKEND`  and `--disable-atomics`.* Removed `pg_ptrack_get_block`.

Ptrack is a fast block-level incremental backup engine for PostgreSQL.Currently `ptrack` codebase is split approximately 50%/50% betweenPostgreSQL core patch and extension. All public SQL API methods areplaced in the `ptrack` extension, while the main engine is still in core.Credits to:* Konstantin Knizhnik* Anastasia Lubennikova* Alexey Kondratov