Address clippy lints currently in beta

src/bin/server.rs

@@ -1,5 +1,5 @@
 #![warn(clippy::all, rust_2018_idioms)]
-#![allow(clippy::unknown_clippy_lints)]
+#![allow(unknown_lints)]
 
 use cargo_registry::{boot, App, Env};
 use std::{

src/models/action.rs

@@ -20,19 +20,19 @@ pub enum VersionAction {
     Unyank = 2,
 }
 
-impl Into<&'static str> for VersionAction {
-    fn into(self) -> &'static str {
-        match self {
+impl From<VersionAction> for &'static str {
+    fn from(action: VersionAction) -> Self {
+        match action {
             VersionAction::Publish => "publish",
             VersionAction::Yank => "yank",
             VersionAction::Unyank => "unyank",
         }
     }
 }
 
-impl Into<String> for VersionAction {
-    fn into(self) -> String {
-        let string: &'static str = self.into();
+impl From<VersionAction> for String {
+    fn from(action: VersionAction) -> Self {
+        let string: &'static str = action.into();
 
         string.into()
     }

src/models/user.rs

@@ -160,11 +160,11 @@ impl User {
     /// Queries the database for the verified emails
     /// belonging to a given user
     pub fn verified_email(&self, conn: &PgConnection) -> QueryResult<Option<String>> {
-        Ok(Email::belonging_to(self)
+        Email::belonging_to(self)
             .select(emails::email)
             .filter(emails::verified.eq(true))
             .first(&*conn)
-            .optional()?)
+            .optional()
     }
 
     /// Queries for the email belonging to a particular user