* new blooms database
* fixed conflict in Cargo.lock
* removed bloomchain
* cleanup in progress
* all tests passing in trace db with new blooms-db
* added trace_blooms to BlockChainDB interface, fixed db flushing
* BlockChainDB no longer exposes RwLock in the interface
* automatically flush blooms-db after every insert
* blooms-db uses io::BufReader to read files, wrap blooms-db into Mutex, cause fs::File is just a shared file handle
* fix json_tests
* blooms-db can filter multiple possibilities at the same time
* removed enum trace/db.rs CacheId
* lint fixes
* fixed tests
* kvdb-rocksdb uses fs-swap crate
* update Cargo.lock
* use fs::rename
* fixed failing test on linux
* fix tests
* use fs_swap
* fixed failing test on linux
* cleanup after swap
* fix tests
* fixed osx permissions
* simplify parity database opening functions
* added migration to blooms-db
* address @niklasad1 grumbles
* fix license and authors field of blooms-db Cargo.toml
* restore blooms-db after snapshot
* secret_store: remove kvdb_rocksdb dependency
* cli: init db mod for open dispatch
* cli: move db, client_db, restoration_db, secretstore_db to a separate mod
* migration: rename to migration-rocksdb and remove ethcore-migrations
* ethcore: re-move kvdb-rocksdb dep to test
* mark test_helpers as test only and fix migration mod naming
* Move restoration_db_handler to test_helpers_internal
* Fix missing preambles in test_helpers_internal and rocksdb/helpers
* Move test crates downward
* Fix missing docs
* cli, db::open_db: move each argument to a separate line
* Use featuregate instead of dead code for `open_secretstore_db`
* Move pathbuf import to open_secretstore_db
Because it's only used there behind a feature gate
