Make example output more legible

[abizjak]

Task description

Running (at least some) examples yields rather hard to understand output, e.g., hashes are not in hex, addresses are not in base58 (see screenshot which is the output of the simple-transfer example)

This should be fixed so that examples output understandable output.

[soerenbf]

The implementation of #308 will probably make this easier to achieve.

[limemloh]

We have toString implementations on most of these types now, so this task would just be to ensure that these looks nice in the output