Bloomchain (#1014)

* use bloomchain crate in blockchain module. remove obsole chainfilter submodule

* update database version to 6.0

* removed redundant line

* simple db migration

* make migration slightly more functional

* bloomchain migration

* migration version is just a single unsigned integer

* updated migration v6

* parity migration

* db migration

* removed hardcoded migration dir

* replace ptr::copy with clone_from_slice, removed potential endianess problem from trace/db.rs

* removed superfluous line

* blockchains log blooms config is not exposed any more

ethcore/src/blockchain/config.rs

@@ -0,0 +1,36 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Blockchain configuration.
+
+/// Blockchain configuration.
+#[derive(Debug)]
+pub struct Config {
+	/// Preferred cache size in bytes.
+	pub pref_cache_size: usize,
+	/// Maximum cache size in bytes.
+	pub max_cache_size: usize,
+}
+
+impl Default for Config {
+	fn default() -> Self {
+		Config {
+			pref_cache_size: 1 << 14,
+			max_cache_size: 1 << 20,
+		}
+	}
+}
+