* Parallelize edge recovery
* Load vertex labels and properties parallel
* Add parallel connectivity loading
* Add batches information to snapshot
* Introduce `items_per_batch` and `recovery_thread_count` flags
* Make possible to load snapshots with old version
* Add vertex batches to `RecoveryInfo`
* Extend durability integration tests with v15 test cases
* Add `std::vector` based `InitProperties`
* Use `InitProperties` in snapshot loading
Summary:
The property store stores a map of `PropertyId` to `PropertyValue` mappings. It
compresses all of the values in order to use as little memory as possible.
Reviewers: teon.banek, ipaljak
Reviewed By: teon.banek
Subscribers: buda, pullbot
Differential Revision: https://phabricator.memgraph.io/D2604
