Fix clippy warnings (#1385)

## Issue Addressed

NA

## Proposed Changes

Fixes most clippy warnings and ignores the rest of them, see issue #1388.

account_manager/src/upgrade_legacy_keypairs.rs

@@ -112,7 +112,7 @@ fn upgrade_keypair<P: AsRef<Path>>(
     let validator_dir = validator_dir.as_ref();
     let secrets_dir = secrets_dir.as_ref();
 
-    let keypair: Keypair = load_unencrypted_keypair(validator_dir.join(input_filename))?.into();
+    let keypair: Keypair = load_unencrypted_keypair(validator_dir.join(input_filename))?;
 
     let password = rand::thread_rng()
         .sample_iter(&Alphanumeric)
@@ -136,7 +136,7 @@ fn upgrade_keypair<P: AsRef<Path>>(
         .to_json_writer(&mut file)
         .map_err(|e| format!("Cannot write keystore to {:?}: {:?}", keystore_path, e))?;
 
-    let password_path = secrets_dir.join(format!("{}", keypair.pk.as_hex_string()));
+    let password_path = secrets_dir.join(keypair.pk.as_hex_string());
 
     if password_path.exists() {
         return Err(format!("{:?} already exists", password_path));

account_manager/src/validator/deposit.rs

@@ -1,6 +1,5 @@
 use crate::VALIDATOR_DIR_FLAG;
 use clap::{App, Arg, ArgMatches};
-use clap_utils;
 use deposit_contract::DEPOSIT_GAS;
 use environment::Environment;
 use futures::compat::Future01CompatExt;

account_manager/src/validator/mod.rs

@@ -28,11 +28,9 @@ pub fn cli_run<T: EthSpec>(matches: &ArgMatches, env: Environment<T>) -> Result<
     match matches.subcommand() {
         (create::CMD, Some(matches)) => create::cli_run::<T>(matches, env, base_wallet_dir),
         (deposit::CMD, Some(matches)) => deposit::cli_run::<T>(matches, env),
-        (unknown, _) => {
-            return Err(format!(
-                "{} does not have a {} command. See --help",
-                CMD, unknown
-            ));
-        }
+        (unknown, _) => Err(format!(
+            "{} does not have a {} command. See --help",
+            CMD, unknown
+        )),
     }
 }

account_manager/src/wallet/create.rs

@@ -117,24 +117,24 @@ pub fn cli_run(matches: &ArgMatches, base_dir: PathBuf) -> Result<(), String> {
     }
 
     println!("Your wallet's 12-word BIP-39 mnemonic is:");
-    println!("");
+    println!();
     println!("\t{}", mnemonic.phrase());
-    println!("");
+    println!();
     println!("This mnemonic can be used to fully restore your wallet, should ");
     println!("you lose the JSON file or your password. ");
-    println!("");
+    println!();
     println!("It is very important that you DO NOT SHARE this mnemonic as it will ");
     println!("reveal the private keys of all validators and keys generated with  ");
     println!("this wallet. That would be catastrophic.");
-    println!("");
+    println!();
     println!("It is also important to store a backup of this mnemonic so you can ");
     println!("recover your private keys in the case of data loss. Writing it on ");
     println!("a piece of paper and storing it in a safe place would be prudent.");
-    println!("");
+    println!();
     println!("Your wallet's UUID is:");
-    println!("");
+    println!();
     println!("\t{}", wallet.wallet().uuid());
-    println!("");
+    println!();
     println!("You do not need to backup your UUID or keep it secret.");
 
     Ok(())

account_manager/src/wallet/mod.rs

@@ -30,11 +30,9 @@ pub fn cli_run(matches: &ArgMatches) -> Result<(), String> {
     match matches.subcommand() {
         (create::CMD, Some(matches)) => create::cli_run(matches, base_dir),
         (list::CMD, Some(_)) => list::cli_run(base_dir),
-        (unknown, _) => {
-            return Err(format!(
-                "{} does not have a {} command. See --help",
-                CMD, unknown
-            ));
-        }
+        (unknown, _) => Err(format!(
+            "{} does not have a {} command. See --help",
+            CMD, unknown
+        )),
     }
 }