* Update a few dependencies
Updates two dependencies: `kvdb-rocksdb` and `h2`. Brings in `parking_lot 0.9` which is unintended but possibly fine.
* Bump parking_lot to 0.9
Bump kvdb-memorydb to 0.2 (from git atm)
* New kvdb-memorydb is not breaking
* Remove [patch]
* Move snapshot to own crate
Sort out imports
* WIP cargo toml
* Make snapshotting generic over the client
Sort out tests
* Sort out types from blockchain and client
* Sort out sync
* Sort out imports and generics
* Sort out main binary
* Fix sync test-helpers
* Sort out import for secret-store
* Sort out more imports
* Fix easy todos
* cleanup
* Move SnapshotClient and SnapshotWriter to their proper places
Sort out the circular dependency between snapshot and ethcore by moving all snapshot tests to own crate, snapshot-tests
* cleanup
* Cleanup
* fix merge issues
* Update ethcore/snapshot/snapshot-tests/Cargo.toml
Co-Authored-By: Andronik Ordian <write@reusable.software>
* Sort out botched merge
* Ensure snapshot-tests run
* Docs
* Fix grumbles
