Standardize on 'use log::*' for easy access to all log level macros

tests/crds_gossip.rs

@@ -1,6 +1,6 @@
 use bincode::serialized_size;
 use hashbrown::HashMap;
-use log::trace;
+use log::*;
 use rayon::prelude::*;
 use solana::cluster_info::NodeInfo;
 use solana::contact_info::ContactInfo;

tests/tvu.rs

@@ -1,7 +1,7 @@
 #[macro_use]
 extern crate solana;
 
-use log::trace;
+use log::*;
 use solana::bank_forks::BankForks;
 use solana::blocktree::{get_tmp_ledger_path, Blocktree};
 use solana::blocktree_processor::BankForksInfo;