Run cargo clippy on whole project (#322)

* Run cargo clippy on plume-common

Run clippy on plume-common and adjuste code accordingly

* Run cargo clippy on plume-model

Run clippy on plume-model and adjuste code accordingly

* Reduce need for allocation in plume-common

* Reduce need for allocation in plume-model

add a quick compilation failure if no database backend is enabled

* Run cargo clippy on plume-cli

* Run cargo clippy on plume

plume-cli/src/users.rs

@@ -70,8 +70,8 @@ fn new<'a>(args: &ArgMatches<'a>, conn: &Connection) {
         username,
         display_name,
         admin,
-        bio,
+        &bio,
         email,
-        User::hash_pass(password),
+        User::hash_pass(&password),
     ).update_boxes(conn);
 }