change the old pictures showing fusiondirectory 1.0.8 in the manual

Hello,

we have some very old pictures int the dev manual that should be replaced

https://fusiondirectory-developer-documentation.readthedocs.io/en/1.4/pluginsystem/start.html#basic-plugin-writing

https://fusiondirectory-developer-documentation.readthedocs.io/en/1.4/pluginsystem/attributes.html