This is just an example of how it could be done. I
based it off how the uninstall process works for the
plugins that I have done.
Note: if another plugin relies on the journal plugin
being installed, this uninstall process does NOT
check for that. And I don't know how it could (never
investigated it, and have no plans to). If someone is
sure they want to uninstall a plugin then they should
atleast do the research to make sure their system can
survive without it.