Add SensitiveUrl to redact user secrets from endpoints (#2326)

## Issue Addressed

#2276 

## Proposed Changes

Add the `SensitiveUrl` struct which wraps `Url` and implements custom `Display` and `Debug` traits to redact user secrets from being logged in eth1 endpoints, beacon node endpoints and metrics.

## Additional Info

This also includes a small rewrite of the eth1 crate to make requests using `Url` instead of `&str`. 
Some error messages have also been changed to remove `Url` data.

lcli/Cargo.toml

@@ -39,3 +39,4 @@ account_utils = { path = "../common/account_utils" }
 eth2_wallet = { path = "../crypto/eth2_wallet" }
 web3 = "0.14.0"
 eth1_test_rig = { path = "../testing/eth1_test_rig" }
+sensitive_url = { path = "../common/sensitive_url" }

lcli/src/eth1_genesis.rs

@@ -2,6 +2,7 @@ use clap::ArgMatches;
 use environment::Environment;
 use eth2_network_config::Eth2NetworkConfig;
 use genesis::{Eth1Config, Eth1GenesisService};
+use sensitive_url::SensitiveUrl;
 use ssz::Encode;
 use std::cmp::max;
 use std::path::PathBuf;
@@ -50,7 +51,11 @@ pub fn run<T: EthSpec>(mut env: Environment<T>, matches: &ArgMatches<'_>) -> Res
 
     let mut config = Eth1Config::default();
     if let Some(v) = endpoints.clone() {
-        config.endpoints = v;
+        config.endpoints = v
+            .iter()
+            .map(|s| SensitiveUrl::parse(s))
+            .collect::<Result<_, _>>()
+            .map_err(|e| format!("Unable to parse eth1 endpoint URL: {:?}", e))?;
     }
     config.deposit_contract_address = format!("{:?}", spec.deposit_contract_address);
     config.deposit_contract_deploy_block = eth2_network_config.deposit_contract_deploy_block;