Updated readme example to use correct mime for the filetype used later in the example

README.md

@@ -16,13 +16,13 @@ func main() {
   mc := mailcap.NewMailcap()
 
   // Find an avialable command with the required key and gui avialability
-  command, err := mc.FindMatch("text/plain", "edit", false)
+  command, err := mc.FindMatch("text/csv", "edit", false)
   if err != nil {
     panic(err)
   }
 
   // Run the command with the filepath provided
-  err := command.Execute("/var/www/index.html")
+  err := command.Execute("/var/www/data/some_data.csv")
   if err != nil {
     panic(err)
   }