Updated Release notes (markdown)

Release-notes.md

@@ -1,3 +1,35 @@
+# v5.5.0
+
+**Release notes for v5.5**
+
+v5.5 is the new long term backend implementation of Invoice Ninja. In this major release we have incremented the minimum PHP to 8.1 and use the Laravel 9 framework this to allows the platform to remain stable without another major platform upgrade until 2024.
+
+How do I upgrade?
+
+First, upgrade your version of PHP to 8.1 and ensure the same extensions are available:
+
+bcmath extension
+ctype extension
+fileinfo extension
+gd extension
+json extension
+mbstring extension
+openssl extension
+PDO extension
+tokenizer extension
+xml extension
+curl extension
+zip extension
+gmp extension
+mysql extension
+fpm (for Nginx)
+
+Update your nginx configuration to point to the new PHP 8.1 FPM socket
+
+If you run multiple version of PHP for other applications on your server, you'll want to ensure the CLI version for invoice ninja is PHP 8.1, if the default PHP cli version is not PHP 8.1 you'll want to update your supervisord configuration to point to the php8.1 binary
+
+After starting the PHP8.1 FPM service and restarting nginx, you are ready to copy over the new v5.5 release files. You can either use the in app upgrade option, or manually copy over release files from the github release section.
+
 # v5.4.12
 
 Minor fixes in this release. **Please note this is the final v5.4.x release.** The next release 5.5 is a major "breaking change" version where we are enforcing the minimum PHP requirements to 8.1 and moving the framework from Laravel 8 to Laravel 9. If you are not ready to change your PHP version up to 8.1 you'll want to stay on the v5.4.12 branch until ready to upgrade.