It's important for NeoGo to have clean documentation. No functional changes.
Right now a bizarre error message can occur if an address flag was not set: `wallet contains no account for 'AFmseVrdL9f9oyCzZefL9tG6UbvhPbdYzM'`. This bug is 10x worse if it occures in `transfer` --from flag.
This makes code less verbose and performs all parsing before invoking main function.