README: update with some basic content

Screenshot coming later

README.md

@@ -1 +1,35 @@
-# WIP Authenticator + Rust
+<a href="https://flathub.org/apps/details/com.belmoussaoui.Authenticator">
+<img src="https://flathub.org/assets/badges/flathub-badge-i-en.png" width="190px" />
+</a>
+
+# Authenticator
+
+<img src="https://gitlab.gnome.org/bilelmoussaoui/authenticator/raw/master/data/icons/com.belmoussaoui.Authenticator.svg" width="128px" height="128px" />
+<p>Two-factor Authentication passwords generator</p>
+
+## Screenshots
+
+![screenshot](data/screenshots/screenshot3.png)
+
+## Features
+
+- Time-based/Counter-based methods support
+- SHA1/SHA256/SHA512 algorithms support
+- QR code scanner
+- Lock the application with a password
+- Beautiful UI
+- Backup/Restore from/into known applications like FreeOTP+, andOTP, Bitwarden
+
+## Getting in touch
+
+If you have any questions regarding the use or development of Authenticator, please join us on our [#authenticator:gnome.org](https://matrix.to/#/#authenticator:gnome.org) channel.
+
+## Hack on Authenticator
+
+To build the development version of Authenticator and hack on the code
+see the [general guide](https://wiki.gnome.org/Newcomers/BuildProject)
+for building GNOME apps with Flatpak and GNOME Builder.
+
+## Credits
+
+- We ship a database of providers based on [twofactorauth](https://github.com/2factorauth/twofactorauth), by the 2factorauth team