Add Playtime App Screenshot to README (#142)

* Add Playtime App Screenshot to README

* Add playtime app screenshot in README
inorder to reduce confusion caused due to the
app not looking like the playtime homepage.

Closes #137

* Resize screenshot and remove redundant text from README.

Author: JacksonIsaac

README.md

@@ -22,7 +22,7 @@ throughout DC. This application will allow donors to view the organization's
 Amazon wish lists, add items, track contributions, and aid staff in following
 up with donors.
 
-*We don't have a live site yet. Stay tuned!*
+![Playtime Project App](doc/playtime_app.png)
 
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