add: Added user param to .bank balance command, but only Bot Owner can use it

src/NadekoBot/data/strings/responses/responses.en-US.json

@@ -1040,6 +1040,7 @@
   "medusa_already_loaded": "Medusa {0} is already loaded",
   "medusa_invalid_not_found": "Medusa with that name wasn't found or the file was invalid",
   "bank_balance": "You have {0} in your bank account.",
+  "bank_balance_other": "User {0} has {1} in the bank.",
   "bank_deposited": "You deposited {0} to your bank account.",
   "bank_withdrew": "You withdrew {0} from your bank account.",
   "bank_withdraw_insuff": "You don't have sufficient {0} in your bank account.",