closes https://github.com/spesmilo/electrum/issues/10119
also:
- wallet.get_onchain_history was broken with from_height/to_height args
- "show_fees" param is and was non-existent. fees are always added to output
- MyEncoder(json.JSONEncoder) changed a bit:
- I am pretty sure cutting the last 3 chars was intended to cut off the seconds
- however that was making incorrect assumptions about what datetime.isoformat() returns
- which depends on whether microsecond precision is available or whether an explicit timezone is set
- this now makes it clear that we want minutes-resolution, but still leaves the timezone-ambiguity
d7c76b991b