update favicon and add readme

Author: Adam

README.md

@@ -0,0 +1,12 @@
+<p align="center">
+  <img src="./public/icon.png" width="64px" />
+</p>
+
+# Mob Timer
+
+A Mob Programming timer!
+
+## Development
+
+1. `yarn` - Install dependencies.
+1. `yarn start` - Start development server.

public/favicon.ico

@@ -10,7 +10,7 @@
       homescreen on Android. See https://developers.google.com/web/fundamentals/engage-and-retain/web-app-manifest/
     -->
   <link rel="manifest" href="%PUBLIC_URL%/manifest.json">
-  <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">
+  <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico?v=3">
   <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,400,500">
   <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
   <!--