Make select-options in Form more configurable

Added getter function getLastlevel() in Doku_Renderer_xhtml.

Translation update (fi)

Now classes and data- attributes can be added to individual options

If external link inserted with link wizard, empty input

Translation update (fr)

Translation update (ko)

Fixes #1483

This is required for the filelist plugin to fix issue #11 since $lastlevel became protected in "hrun".

Add a protected file to the authplain config cascade

autoload plugin namespace

Remove unnecessary linebreaks from new Form

Fix caching issue in wikiFN

Allow true/false for onoff config setting

preg_replace eval modifier

See #1551

Changed the values recognized by the general config parser.
If value in config is a boolean it is recognized as boolean, not if it
is a string.

Fixes #718

Since Firebug it is no longer necessary to structure html with linebreaks. See also Issue #924

as pointed out in
https://github.com/splitbrain/dokuwiki/pull/1530/files/b89dfc20f1e13333ce49ce0d6a3a83cc9836094b#r60392099

Caching must differentiate between a call with $ascii == true and a call
without that parameter. Since calling that function with $ascii == true
rare, we simply do not cache that case.

Remove support for 'disabled' in plugin folder

This `$conf['pluginmanager']` setting was especially for disabling of
pluginmanager in farms. (see also commit c45608df )

remaining folders with .disabled in the foldername are displayed in
extension manager with rename warning.

The opera work around is still needed though! O_o

Standardized node.textContent is available since IE9