Separate migrations from util (#6690)

* separate migration from util and make its dependencies into libs:

* snappy
* kvdb
* error
* common

* renamed common -> macros

* util error does not depend on snappy module

* ethsync does not depend on util nor ethcore_error

* nibbleslice and nibblevec merged with patricia_trie crate

* removed unused dependencies from util

* util journaldb traits does not need to be public

* util_error

* fixed ethcore compile error

* ignore .swo files

* Update chain.rs

ethcore/src/tests/client.rs

@@ -27,6 +27,7 @@ use tests::helpers::*;
 use types::filter::Filter;
 use bigint::prelude::U256;
 use util::*;
+use kvdb::{Database, DatabaseConfig};
 use devtools::*;
 use miner::Miner;
 use spec::Spec;

ethcore/src/tests/helpers.rs

@@ -231,8 +231,8 @@ pub fn get_test_client_with_blocks(blocks: Vec<Bytes>) -> Arc<Client> {
 	client
 }
 
-fn new_db() -> Arc<KeyValueDB> {
-	Arc::new(::util::kvdb::in_memory(::db::NUM_COLUMNS.unwrap_or(0)))
+fn new_db() -> Arc<::kvdb::KeyValueDB> {
+	Arc::new(::kvdb::in_memory(::db::NUM_COLUMNS.unwrap_or(0)))
 }
 
 pub fn generate_dummy_blockchain(block_number: u32) -> BlockChain {

ethcore/src/tests/trace.rs

@@ -27,7 +27,7 @@ use client::*;
 use tests::helpers::*;
 use devtools::RandomTempPath;
 use client::{BlockChainClient, Client, ClientConfig};
-use util::kvdb::{Database, DatabaseConfig};
+use kvdb::{Database, DatabaseConfig};
 use std::sync::Arc;
 use header::Header;
 use miner::Miner;