Clarify `getAddressSummary` response ambiquity

[braydonf]

Several of the results returned from the getAddressSummary method have different possible interpretations:

• "unconfirmedBalance" : "confirmed balance + unconfirmed transactions" vs. "unconfirmed delta"
• "appearances" : "number of inputs/outputs" vs. "total transaction ids"
• "totalReceived" : "received from another address" vs. "received"

[levino]

This was kinda solved, not? Now it looks that the unconfirmed balance can get negative. Makes no sense but one can work around from there and add "balance" and "unconfirmedBalance" to get what is interesting: the balance that everyone in the network agrees on.

Referencing #363