feat: adds Mercedess user stories for lesson05 (#183)

Author: mercedes-mathews

lesson_05/mercedesmathews/README.md

@@ -0,0 +1,5 @@
+# User stories for a music platform when walking and running
+
+- As a runner, I want an app to track how fast i'm running, so that it can play music that matches my pace.
+- As a spotify listener, I want the app to link with my spotify, so that it can play music from my own playlists.
+- As a user, I want to add my music preferences, so that the app can generate music based off of them.