okay. I can't read. we already had a multiline config. It's the default.
So I reverted my change, except for making use of formText/cleanText for
proper line ending handling and I added made focused textareas a bit
larger.

* code/PHP5 cleanup

* fixes merge messup (code was made up from parts of authad)
* code and PHP5 cleanup

* use proper plugin config
* code/PHP5 cleanup

* makes proper use of plugin config
* adds a few first defaults, but the whole config metadata is still
  missing
* proper PHP5 use and comments

* fixes incorrect $this->adldap calls
* makes use of correct plugin config

This does nothing currently but allows us adding certain things
to the base class later.

added missing info.txt parameters, added plugin plugin's info.txt, adjusted old default  template's description

FIX for FS#2463 <https://bugs.dokuwiki.org/index.php?do=details&task_id=2463>