update readme

Author: bangnokia

README.md

@@ -1,6 +1,8 @@
 # blademail
 
-Local SMTP desktop app for debugging and previewing your emails.
+Blade Mail is an Local SMTP desktop app for debugging and previewing your emails.
+
+This is the repository of the Blade Mail app. If you like this app, you can buy at [blademail.app](https://blademail.app). I'm only selling the built version of this app.
 
 **This is not Electron!**, and file size is small!
 ![](/blade-mail-screenshot.png)