Hash Content RPC method (#2355)

* Moving file fetching to separate crate.

* ethcore_hashContent

* Tests running on mocked fetch.

* Limiting size of downloadable assets

util/fetch/src/lib.rs

@@ -0,0 +1,29 @@
+// 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/>.
+
+//! A service to fetch any HTTP / HTTPS content.
+
+#[macro_use]
+extern crate log;
+extern crate hyper;
+extern crate https_fetch;
+extern crate rand;
+
+
+pub mod client;
+pub mod fetch_file;
+
+pub use self::client::{Client, Fetch, FetchError, FetchResult};