Feature request: Anonymize logging

[shsmith]

Add a setting to enable anonymized logging. When enabled, the logs will omit IP addresses, TX hashes and any other information that could potentially identify a connected user. This would also apply to the stdout and stderr streams.

[szhongben]

Collect or contribute bitcoins for resolving this issue via Synapsi

[bauerj]

See #134.

That PR removes IP addresses from the log file. There isn't anything else that would be of much help in identifying users.

TX hashes will only be printed in case of errors (e.g. invalid transaction) but without user information. That is quite helpful in debugging errors and Bitcoin transactions are not secret anyway so I didn't change that.

[ahmedbodi]

done here: https://github.com/spesmilo/electrum-server/pull/138