Use edition 2018.

Cargo.toml

@@ -13,6 +13,7 @@ documentation = "https://docs.rs/jid"
 readme = "README.md"
 keywords = ["xmpp", "jid"]
 license = "LGPL-3.0+"
+edition = "2018"
 
 [badges]
 gitlab = { repository = "xmpp-rs/jid-rs" }

src/lib.rs

@@ -4,7 +4,6 @@
 //!
 //! For usage, check the documentation on the `Jid` struct.
 
-extern crate failure;
 #[macro_use] extern crate failure_derive;
 
 use std::fmt;
@@ -381,9 +380,6 @@ impl Jid {
 
 }
 
-#[cfg(feature = "minidom")]
-extern crate minidom;
-
 #[cfg(feature = "minidom")]
 use minidom::{IntoAttributeValue, IntoElements, ElementEmitter};