Upgrade elastic-array to 0.9.0

This is a huge change, which includes some changes to replace code that
originally cloned to reuse allocations instead. The updated
`elastic-array` crate renames its consuming `Vec`-conversion method to
`into_vec`, which means that I can do a simple
`sed -i 's/to_vec/into_vec/'` and then fix the compilation errors.

This commit is probably a minor performance win and definitely a
significant readability win.

util/rlp/Cargo.toml

@@ -7,7 +7,7 @@ version = "0.2.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 
 [dependencies]
-elastic-array = "0.8"
+elastic-array = "0.9"
 ethcore-bigint = { path = "../bigint" }
 lazy_static = "0.2"
 rustc-serialize = "0.3"

util/rlp/src/lib.rs

@@ -98,7 +98,7 @@ pub fn decode_list<T>(bytes: &[u8]) -> Vec<T> where T: Decodable {
 ///
 /// fn main () {
 /// 	let animal = "cat";
-/// 	let out = rlp::encode(&animal).to_vec();
+/// 	let out = rlp::encode(&animal).into_vec();
 /// 	assert_eq!(out, vec![0x83, b'c', b'a', b't']);
 /// }
 /// ```

util/rlp/src/stream.rs

@@ -264,8 +264,8 @@ impl RlpStream {
 	/// panic! if stream is not finished.
 	pub fn out(self) -> Vec<u8> {
 		match self.is_finished() {
-			//true => self.encoder.out().to_vec(),
-			true => self.buffer.to_vec(),
+			//true => self.encoder.out().into_vec(),
+			true => self.buffer.into_vec(),
 			false => panic!()
 		}
 	}