Merge #11886: Clarify getbalance meaning a tiny bit in response to questions.

c79d73d Clarify getbalance meaning a tiny bit in response to questions. (Matt Corallo)

Pull request description:

  Someone was asking why getbalance "*" was more "correct" than getbalance, which should rarely be true...spendzeroconfchange was the issue.

Tree-SHA512: 90201cad1acec5161aee469fb4c6d737a0eb90f8380ac93abf0e41e0f02d120afcc3e2e873e5096d3655bb63bbd16fe99e72452f308d72e69139c7f6bb2d745e

src/wallet/rpcwallet.cpp

@@ -771,6 +771,8 @@ UniValue getbalance(const JSONRPCRequest& request)
         throw std::runtime_error(
             "getbalance ( \"account\" minconf include_watchonly )\n"
             "\nIf account is not specified, returns the server's total available balance.\n"
+            "The available balance is what the wallet considers currently spendable, and is\n"
+            "thus affected by options which limit spendability such as -spendzeroconfchange.\n"
             "If account is specified (DEPRECATED), returns the balance in the account.\n"
             "Note that the account \"\" is not the same as leaving the parameter out.\n"
             "The server total may be different to the balance in the default \"\" account.\n"