Remove support for Vue 2 (#217)

* Removed support for vue 2
* Updated to latest keycloak-js version
* Added `useKeycloak()` function to get a reactive object for the
keycloak instance
* Move to use vite for building plugin
* Updated README's and examples

---------

Co-authored-by: Chris Aurora Neumann Ruud <66010392+chrisnruud@users.noreply.github.com>

CONTRIBUTING.md

@@ -1,9 +1,10 @@
-## Important notice about the state of this project from the maintainers
+## Important Notice from the Maintainers
 
-This project started at one time as a utility wrapper for keycloak.js as a simpler way to instantiate keycloak
-in the projects developed by [@dsb-norge](https://github.com/dsb-norge) , and our usage is tied to whatever 
-version of keycloak is supplied by RedHat SSO. This again means that later versions of keycloak will not be
-available for testing by the maintainers, and thus will not likely be supported or implemented by this project.
+This project began as a utility wrapper for `keycloak-js`, providing a simpler way to instantiate Keycloak in projects developed by [@dsb-norge](https://github.com/dsb-norge).
+We are currently transitioning from RedHat SSO to Keycloak, allowing us to update the `keycloak-js` adapter to the latest version of keycloak.
 
-Since this project has gained some traction out there in the OSS landscape, we feel like we are doing the community a disservice by
-letting the project go stale without communicating clearly what the initial goals were, and the current state of maintenance.
+However, we will soon be moving away from Keycloak as well. Consequently, the project will eventually become stale, as we will no longer be able to verify or test changes or updates.
+
+Given the traction this project has gained in the OSS community, we want to clearly communicate the initial goals and the current state of maintenance to avoid any confusion.
+
+Thank you for your understanding and support.