Update README

Author: overflowy

README.md

@@ -1,2 +1,15 @@
-# null-pointer-client
-Simple GO client for [The Null Pointer](https://0x0.st/)
+# npu
+
+# [![npu](static/screenshot.png)](https://github.com/overflowy/null-pointer-uploader)
+
+Simple GO client for [The Null Pointer](https://0x0.st/) file-sharing service.
+
+## How it works
+
+When executed, the program reads the specified file and creates a multipart/form-data POST request to send to the 0x0.st API. The uploaded file is included as a form file with the name file. The expiration and secret options, if specified, are also included as form fields.
+
+Upon a successful upload, the program outputs the URL to the uploaded file to the console and also writes it to the clipboard.
+
+## License
+
+The code in this repository is licensed under the MIT License. See LICENSE for more information.