Add comma to match a later section
CB-7977 Mention deviceready in plugin docs
CB-8018 Add vibrate(pattern) fallback on vibrate for Windows Phone 8

Added vibrate(pattern) fallback on vibrate for Windows Phone 8
Added vibration cancelling support for Windows Phone 8
CB-7970 Add cordova-plugin-vibration support for Windows Phone 8.1

Added Windows Phone 8.1 support
Updated documentation