Adminneo has redone the whole structure and removed any naming notion of
adminer. This includes now a different plugin mechanism, a new
configuration mechanism etc.
For this matter:
* Removed support for individualizing plugins (this is better left for a module)
* Removed support for themes (no longer exists in adminneo)
* Removed the special index.php (a link is kept, though)
* Installed all default plugins by default. This does not activate
them.
Other changes:
* Update homepage
* Add myself as maintainer