Add Zap Yeti to ecosystem and include logo (#32)

* Add EnvelopeBudget to ecosystem and include logo

* Add ZapYeti to ecosystem page

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Co-authored-by: Dustin Davis <dustin@canaryspeech.com>

Author: djedi

ecosystem.md

@@ -91,6 +91,11 @@ To add to this list, <a href="https://github.com/simplefin/simplefin.github.com/
   <div class="item-desc">Simple Budgeting, Powerful Results</div>
 </a>
 
+<a class="item" href="https://zapyeti.com" target="_blank">
+  <div class="item-title"><img src="/img/applogos/zapyeti.png" title="ZapYeti logo"> ZapYeti</div>
+  <div class="item-desc">Debt payoff calculator and tracker</div>
+</a>
+
 <a class="item" href="https://envelopebudget.com" target="_blank">
   <div class="item-title"><img src="/img/applogos/envelopebudget.png" title="EnvelopeBudget logo"> EnvelopeBudget</div>
   <div class="item-desc">Envelope method for the digital age</div>