Disable WAL (#1765)

* Disable WAL

* Make WAL optional

* Fix tests.

* Update cli.rs

ethcore/src/client/client.rs

@@ -176,6 +176,7 @@ impl Client {
 		let mut db_config = DatabaseConfig::with_columns(DB_NO_OF_COLUMNS);
 		db_config.cache_size = config.db_cache_size;
 		db_config.compaction = config.db_compaction.compaction_profile();
+		db_config.wal = config.db_wal;
 
 		let db = Arc::new(Database::open(&db_config, &path.to_str().unwrap()).expect("Error opening database"));
 		let chain = Arc::new(BlockChain::new(config.blockchain, &gb, db.clone()));

ethcore/src/client/config.rs

@@ -101,6 +101,8 @@ pub struct ClientConfig {
 	pub db_cache_size: Option<usize>,
 	/// State db compaction profile
 	pub db_compaction: DatabaseCompactionProfile,
+	/// Should db have WAL enabled?
+	pub db_wal: bool, 
 	/// Operating mode
 	pub mode: Mode,
 	/// Type of block verifier used by client.