Display transaction fees in normal mode

[murisi]

A Namada transaction might consume more fees than a user expects. For this reason we should display transaction fees in normal mode. Transaction fees are computed as WrapperTx::fee.amount_per_gas_unit * WrapperTx::gas_limit. Please find attached the test vectors and debug vectors with transaction fees displayed in normal mode: testdbgs (copy 1).txt.gz and testvecs(1).json .