Confirm whitelist vs. blacklist options for Redux data in local storage

[corquaid]

Follow-on issue from #40:

Tom: I'm wondering whether the whitelist would be a better option... whitelist is safer, but blacklist is more convenient. Also, whitelist decreases a chance that we will store large amount of data. I could not find any information about restrictions on the localStorage size in Tauri, usually it is about 10 Mb in web browsers.

Tarnas: yes, whitelist is safer, but I was lazy, we can come back to it and check it again, there's a possibility that once we start to collect performance stats etc. we'll have to revisit this and change the way we persist store, but it's a small change we can always do

[tomaszantas]

Reviewed this concern and the localStorage data:

• credentials are not present in the localStorage (wallet password and merged/monero authentication)
• due to small number of credentials used in the app, and dedicated Redux store: credentials that is blacklisted, the blacklist approach is more convenient.