Adds Budzet Zen to Budgeting Tools (#149)

* Add Budget Zen - End-to-End Encrypted Budget/Expense Manager

Full disclosure: I'm the author of [Budget Zen](https://budgetzen.net).

Budget Zen 2.0 is end-to-end encrypted via [userbase](https://userbase.com). You can read more about [that announcement here](https://news.onbrn.com/announcing-budget-zen-2.0-end-to-end-encrypted).

It's also Open Source (AGPL 3.0), and you can [view the source code in GitHub](https://github.com/BrunoBernardino/budgetzen-web).

* Updates BudgetZen

Moves to notable mentions until the project is more mature

Co-authored-by: Alicia Sykes <alicia@omg.lol>

README.md

@@ -1169,7 +1169,7 @@ Note that credit card providers heavily track transaction metadata, which build
 #### Notable Mentions
 Spreadsheets remain a popular choice for managing budgets and financial planning.  [Collabora](https://nextcloud.com/collaboraonline) or [OnlyOffice](https://nextcloud.com/onlyoffice) (on [NextCloud](https://nextcloud.com)), [Libre Office](https://www.libreoffice.org) and [EtherCalc](https://ethercalc.net) are popular open source spread sheet applications. [Mintable](https://github.com/kevinschaich/mintable) allows you to auto-populate your spreadsheets from your financial data, using publicly accessible API - mitigating the requirement for a dedicated budgeting application.
 
-Other notable open source budgeting applications include: [Smart Wallet](https://apps.apple.com/app/smart-wallet/id1378013954) (iOS), [My-Budget](https://rezach.github.io/my-budget) (Desktop), [MoneyManager EX](https://www.moneymanagerex.org), [Skrooge](https://skrooge.org), [kMyMoney](https://kmymoney.org)
+Other notable open source budgeting applications include: [Smart Wallet](https://apps.apple.com/app/smart-wallet/id1378013954) (iOS), [My-Budget](https://rezach.github.io/my-budget) (Desktop), [MoneyManager EX](https://www.moneymanagerex.org), [Skrooge](https://skrooge.org), [kMyMoney](https://kmymoney.org) and [Budget Zen](https://budgetzen.net) (a simple E2E encrypted budget manager)
 
 See Also: [Cryptocurrencies](#cryptocurrencies), [Virtual Credit Cards](#virtual-credit-cards) and [Other Payment Methods](#other-payment-methods)