Optional Tor Send/Listen Functionality (#226)

* udpate for beta release

* initial tor explorations

* rustfmt

* basic tor tx send working

* rustfmt

* add tor proxy info to config file

* rustfmt

* add utilities to output tor hidden service configuration files

* output tor config as part of listener startup

* rustfmt

* fully automate config and startup of tor process

* rustfmt

* remove unnecessary process kill commands from listener

* rustfmt

* assume defaults for tor sending config if section doesn't exist in grin-wallet.toml

* rustfmt

* ignore tor dev test

* update default paths output by config, compilation + confirmed working on windows

* rustfmt

* fix on osx/unix

* add timeout to tor connector, remove unwrap in client

* allow specifiying tor address without 'http://[].onion' on the command line

* fix api test

* rustfmt

* update address derivation path as per spec

* rustfmt

* move tor init to separate function

* rustfmt

* re-ignore tor dev test

* listen on tor by default if tor available

* rustfmt

* test fix

* remove explicit send via tor flag, and assume tor if address fits

* rustfmt

impls/src/error.rs

@@ -16,6 +16,7 @@
 use crate::core::libtx;
 use crate::keychain;
 use crate::libwallet;
+use crate::util::secp;
 use failure::{Backtrace, Context, Fail};
 use std::env;
 use std::fmt::{self, Display};
@@ -45,6 +46,10 @@ pub enum ErrorKind {
 	#[fail(display = "IO error")]
 	IO,
 
+	/// Secp Error
+	#[fail(display = "Secp error")]
+	Secp(secp::Error),
+
 	/// Error when formatting json
 	#[fail(display = "Serde JSON error")]
 	Format,
@@ -73,6 +78,14 @@ pub enum ErrorKind {
 	#[fail(display = "{}", _0)]
 	ArgumentError(String),
 
+	/// Generating ED25519 Public Key
+	#[fail(display = "Error generating ed25519 secret key: {}", _0)]
+	ED25519Key(String),
+
+	/// Checking for onion address
+	#[fail(display = "Address is not an Onion v3 Address")]
+	NotOnion,
+
 	/// Other
 	#[fail(display = "Generic error: {}", _0)]
 	GenericError(String),
@@ -151,6 +164,14 @@ impl From<keychain::Error> for Error {
 	}
 }
 
+impl From<secp::Error> for Error {
+	fn from(error: secp::Error) -> Error {
+		Error {
+			inner: Context::new(ErrorKind::Secp(error)),
+		}
+	}
+}
+
 impl From<libwallet::Error> for Error {
 	fn from(error: libwallet::Error) -> Error {
 		Error {