array splice operations are expensive. when many cells in a table row
are missing, the operation should be executed only once instead for each
missing cell.

Default only text string exists, via localized translation a wiki admin
can add his/her own (html) version.

As discussed in Issue #1454 dokuwiki currently "forgets" additional
queryparams when redirecting from devel: to devel:start

Example:
https://www.dokuwiki.org/devel:?foo=bar
should result in
https://www.dokuwiki.org/devel:start?foo=bar
but actually results in
https://www.dokuwiki.org/devel:start

This commit fixes that behaviour.

Fixes #1454

with unittests

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

Let plugins add their own classes to builtin tables or lists.

Fixes #1188
Alternative for #1360 (and PR #1515)

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

RemoteAPICore
- visibility methods
- getAttachmentInfo returns modification date of deleted files
- pageVersions returns only current revision (once) if $first=0.
Adresses issue mentioned at #1550
- added unittests
- updated API number

Fixes #714

Fixes #713

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.

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.

This drops support for Internet Explorer <9 which we no longer support.