Make pruning section more consistent in README.md

use syntax highlighting on commands and command line arguments

README.md

@@ -707,8 +707,8 @@ DNS_PUBLIC=tcp torsocks ./monerod --p2p-bind-ip 127.0.0.1 --no-igd --rpc-bind-ip
 As of May 2020, the full Monero blockchain file is about 80 GB. One can store a pruned blockchain, which is about 28 GB.
 A pruned blockchain can only serve part of the historical chain data to other peers, but is otherwise identical in
 functionality to the full blockchain.
-To use a pruned blockchain, it is best to start the initial sync with --prune-blockchain. However, it is also possible
-to prune an existing blockchain using the monero-blockchain-prune tool or using the --prune-blockchain monerod option
+To use a pruned blockchain, it is best to start the initial sync with `--prune-blockchain`. However, it is also possible
+to prune an existing blockchain using the `monero-blockchain-prune` tool or using the `--prune-blockchain` `monerod` option
 with an existing chain. If an existing chain exists, pruning will temporarily require disk space to store both the full
 and pruned blockchains.