Updated Release notes (markdown)

Release-notes.md

@@ -1,3 +1,36 @@
+# v5.4.0
+
+This is a _big_ release.
+
+Whats new? The self updater has been further improved. With each release a new chromium folder is installed into the application, and when you are releasing at least once a week like we are, these folders start to consume significant space. To fix this, the self updater will now remove all old chromium files/folders in the system.
+
+The Checkout Payment driver has been completely rewritten to take advantage of their new API key system. We now support both the default API and the Four API.
+
+We've added the ability to switch from the Flutter front end to our React front end using the small React button on the dashboard. Please note, this will only work if you use our Release file / Self updater. Please bear in mind that the switch is a one way function at the moment until we update the React Web Application to enable switching back to the Flutter front end.
+
+The Purchase Order API has been completed and we are nearing completion of the front end works for this.
+
+ 
+
+Minor fixes for correct disk configuration when using S3  
+Stubs for vendor portal  
+Fixes for badge color shading  
+Remove old snappdf installations prior to upgrading  
+Accept a purchase order  
+Accept signatures on purchase orders  
+Update composer dependencies  
+Vendor profile update  
+Checkout v2 refactor  
+Minor fixes for recurring invoices  
+Add switch to force react as front end  
+Clean up for self updater  
+Update .gitignore  
+Notifications for Purchase orders / Viewed / Accepted  
+Comments for React Application  
+Don't allow upgrade to react if it is not installed  
+
+
+
 # v5.3.100
 
 Add Vendor guard