I am learning how to develop Confluence blueprint plugins. I just finished the tutorial on this page: https://developer.atlassian.com/server/confluence/write-a-simple-confluence-blueprint-plugin/. This tutorial shows you how to create an xml template and how to refer to it as a resource, in the atlassian-plugin.xml file. Is there any way to use a custom page template -- the one that's in Confluence's database (PAGETEMPLATES) -- instead of an xml file? Or, are we limited to just xml files?