spl-token: provide more useful output when using create-token with the output option and small redesign of token cli architecture (solana-labs#2593)

* spl-token: WIP

* Remove and_then, move tx handling in separate function- output handling still missing

* spl-token: add basic output handling for all calls, add detailed output to create-token

* spl-token: remove changes in bench that are not strictly necessary to remove # of files touched in this PR

* [spl-token] cli: HandleTxReturn is now TransactionReturnData

* [spl-token] cli: Make commands return output String that is printed in fn main()

* [spl-token] cli: remove old todos

* [spl-token] cli: only use no_wait arg in command_transfer and use constant for "create-token"

Author: paul-schaaf

token/cli/src/bench.rs

@@ -1,3 +1,5 @@
+use crate::CommandResult;
+
 /// The `bench` subcommand
 use {
     crate::{
@@ -165,7 +167,7 @@ pub(crate) fn bench_process_command(
     config: &Config,
     mut signers: Vec<Box<dyn Signer>>,
     wallet_manager: &mut Option<Arc<RemoteWalletManager>>,
-) -> Result<(), Error> {
+) -> CommandResult {
     assert!(!config.sign_only);
 
     match matches.subcommand() {
@@ -229,7 +231,7 @@ pub(crate) fn bench_process_command(
         _ => unreachable!(),
     }
 
-    Ok(())
+    Ok("".to_string())
 }
 
 fn get_token_address_with_seed(token: &Pubkey, owner: &Pubkey, i: usize) -> (Pubkey, String) {