UM Guide Updates for 22.04 (#19)

* UM Guide Updates for 22.04

Updated and new content for the 22.04 release

* Update screen shots and fix broken links

Update screen shots and fix broken links

Author: goinglinux

README.md

@@ -10,7 +10,7 @@ The version of this guide provided in Ubuntu MATE release 17.10 and earlier was
 
 With Ubuntu MATE release 18.10 the documentation has been expanded significantly and now uses the *DocBook* format. *DocBook* is also a markup format for creating documentation presented to users with the **Yelp** help system, however the entire documentation is contained in a single file named `index.docbook`. This format appears to be preferred in documentation produced for applications produced by the MATE project. Although the presentation in the help system is slightly different, both the *DocBook* format and the *Mallard* format for documentation can link to one-another and interact nicely in **Yelp**.
 
-The most recent update to the guide incorporates new applications and features of **Ubuntu MATE release 21.04**.
+The most recent update to the guide incorporates new applications and features of **Ubuntu MATE release 22.04**.
 
 ----------
 ## Translations