Add transaction signing with in accounts sub-namespace. (#279)

* implemented accounts.sign and accounts.hashMessage

* Started adding transaction signing

* rustfmt

* added unit test for IntoAccounts trait

* added raw transaction parameter signing

* added transaction signing

* used ethereum-transaction instead of custom types

* cargo fmt

* remove dead code

* add TODO remove the mem::transmute

* into signature changes

* added new recovery data type

* cargo fmt and clippy

* update to latest ethereum-transaction

* rename types, more clippy

* Added ability to get recovery data from raw signature

Cargo.toml

@@ -15,9 +15,12 @@ edition = "2018"
 arrayvec = "0.5.0"
 ethabi = "9.0.0"
 ethereum-types = "0.8.0"
+ethereum-transaction = "0.2.0"
+ethsign = "0.7.3"
 futures = "0.1.26"
 jsonrpc-core = "14.0.0"
 log = "0.4.6"
+parity-crypto = "0.4.2"
 parking_lot = "0.9.0"
 rustc-hex = "2.0.1"
 serde = { version = "1.0.90", features = ["derive"] }