--debug should not display postingWif from a config

[noisy]

The problem

Private posting key is displayed in logs when --debug is used. We should never display any private data in logs

I did

wise --debug download-rules -a lenka ./lenka.yml

I expected to see:

wise --debug download-rules -a lenka ./lenka.yml
log.level["steem-wise-cli"]="debug"
steem-wise-cli | Trying to read config from /home/noisy/.wise/config.yml
steem-wise-cli | Failed to parse config (/home/noisy/.wise/config.yml) as JSON: Unexpected token u in JSON at position 0
steem-wise-cli | Successfully parsed /home/noisy/.wise/config.yml as YAML
steem-wise-cli | Loaded config: {"username":"noisy3","postingWif":"*********************************************************","steemApi":"https://anyx.io","defaultSyncStartBlockNum":28438545,"defaultRulesPath":"rules.yml","syncedBlockNumFile":"synced-block-num.txt","disableSend":false,"configFilePath":"/home/noisy/.wise/config.yml"}
Downloading rules set by @lenka...
Rules saved to file /home/noisy/.wise/lenka.yml

Instead, I saw:

---

Version of steem-wise-core: 3.0.6-rc1
Version of nodejs: 10.0.5

[Jblew]

Done

[noisy]

tested, it looks ok 👍