* Generalize BlockImport
- move ImportBlock, BlockOrigin, ImportResult into shared sr-primitives
- let Consensus provide and traits again
- update consensus traits to latest development
- implement traits on client::Client, test_client::TestClient
- update RHD to use the new import_block API
* Move ImportBlock into consensus-common
* Send import notification in aura tests
* Integrating aura into service
* Make Signatures more generic
* Aura Block Production with the given key
* run aura on the thread pool
* start at exact step start in aura
* Add needed wasm blob, in leiu of better solutions.
* Make API ids consistent with traits and bring upstream for sharing.
* Add decrease_free_balance to Balances module
* Encode `Metadata` once instead of two times
* Bitops include xor
* Upgrade key module.
* Default pages to somewhat bigger.
* Introduce upgrade key into node
* Add `Created` event
* add stub for Client.best_chain_containing_block_hash
* add fn blockchain::Backend::leaf_hashes
* fix typo
* sketch out Client.best_chain_containing_block_hash
* fix indent
* Blockchain.leaf_hashes -> Blockchain.leaves
* add unimplemented! stub impls for Blockchain.leaves
* start impl of Blockchain.leaves for in-memory client db
* Client.best_chain_containing...: check canonical first and make compile
* first rough attempt at maintaining leaf list in in-memory db
* fix tab indent
* add test best_chain_containing_single_block
* add failing test best_chain_containing_with_fork
* pub use client::blockchain; in test-client to prevent circular dep in client tests
* best_chain_containing_with_single_block: improve and test leaves
* far improve in-memory Backend::leaves impl
* test blockchain::Backend::leaves more thoroughly
* handle more edge cases in blockchain::Backend::leaves impl for in memory
* fix test best_chain_containing_with_fork (two distinct test blocks had same hash)
* make best_chain_containing_block_hash pass existing tests
* improve docstring for Blockchain::leaves
* Client.best_chain_containing: some cleanup. support max_block_number
* best_chain_containing: remove broken outcommented fast check for best = canonical
* remove blank line
* best_block_containing: return None if target_hash not found
* best_chain_containing: add unreachable! at end of function
* improve tests for best_chain_containing
* renames
* more elaborate test scenario for best_containing
* best_containing: fix restriction of search through maybe_max_number
* best_containing: tests for restriction of search
* get rid of unnecessary clones
* replace Client::new_in_mem by new_with_backend which is useful for testing backends
* add test_client::new_with_backend for testing different backend impls
* add test for in_mem::Backend::leaves
* remove unused imports
* in_mem test_leaves: simplify
* flesh out tests for in_mem leaves impl
* remove tests for leaves from client which are now covered in implementing module
* improve comment
* add Client.new_in_mem again
* unwrap in test_client::new_with_backend
* make test_client::BlockBuilderExt work not just with in-mem backend
* make test client ext not just work with in mem backend
* add failing Backend.leaves test for client-db
* update Cargo.lock
* replace KeccakHasher with Blake2Hasher
* refactor
address grumble https://github.com/paritytech/substrate/pull/740#discussion_r217822862
* refactor using NumberFor
address grumble https://github.com/paritytech/substrate/pull/740#discussion_r217823341
* add test that exposes possible problem
* update docstring for Client.best_containing
* extract test for Backend.leaves for reuse
* improve test blockchain_header_and_hash_return_blocks_from_canonical_chain_given_block_numbers
* extract test_blockchain_query_by_number_gets_canonical to easily test multiple impls
* remove whitespace
* remove todo
* Client.best_containing: pre-empt search loop when target in canonical
* best_containing: prevent race condition by holding import lock
* add todo
* extract leaf list update code into function
* add comment
* client-db: use in-memory-kvdb for tests
* use BTreeSet to store leaves for in-mem which is faster and simpler
* add docstring
* add comments and fix formatting
* add initial raw version of LeafSet
* remove Client::update_leaves which has been superceded by LeafSet
* use LeafSet in in-mem backend
* keccak -> blake2
* don't reexport codec traits in primitives
addresses https://github.com/paritytech/substrate/pull/740#discussion_r219538185
* fix rebase mistake
* improve LeafSet and use it in state-db
* correct Transfer nonces to fix ApplyExtinsicFailed(Stale)
* use given backend in canoncal test
* kill dead tree-route code in util
* fix warnings
* tests for leafset
* reorganizations in in_mem backend
* fix reorganization canon block logic
* DB commit and safe reversion on write error
* fix style nits
Benjamin Kampmann