update README

Author: sam-mfb

README.md

@@ -1,4 +1,25 @@
-# MFB Typescript Template
+# msal-node-utils
 
-Easy staring place for setting up MFB OSS Typescript packages
+Utilities for easier node msal authentication
 
+## azureTokenGetter
+
+### Authentication
+
+This utility will try get a token silently, and, if that fails, will try interactively, using `open` to open the browser.
+
+### Cache Persistance
+
+This is basically exactly what is described here:
+
+https://github.com/AzureAD/microsoft-authentication-library-for-js/tree/dev/extensions/msal-node-extensions
+
+On linux (including in a linux docker container), I've found it easiest to use gnome-keyring (even if you aren't using Gnome desktop; I'm just using an X server on my host).
+
+I've installed at least
+
+```bash
+sudo apt-get -y dbus-x11 libsecret-1-0 libsecret-1-dev libsecret-tools gnome-keyring xdg-utils
+```
+
+on an Ubuntu 24 docker container.