Added logo image to docs

Author: corneliusyaovi

README.md

@@ -1,3 +1,7 @@
+<p align="center">
+    <img title="Flutterwave" height="200" src="https://flutterwave.com/images/logo-colored.svg" width="50%"/>
+</p>
+
 # Flutterwave Android SDK
 
 Flutterwave's Android SDK can be used to integrate the Flutterwave payment gateway into your android app. It comes with a ready-made Drop In UI and non-UI module, depending on your preference.