Fix longstanding issue with cache class & cachetime setting

1. cachetime setting should only be applied to the cache_renderer
   class.  Previously it was applied to cache_parser (and by
   extension cache_handler).
2. two special cachetime values, -1 & 0, weren't handled, per
   FS#2183

To handle the cachetime setting, -1, disable caching, a new
property _nocache is added.  When that property is true, any cache
file must not be used and storecache() should not store any values
put PHPDocs comment back the way it should be
adjust logic of caching comments for _nocache
translation update
translation update
translation update
Merge pull request #670 from dokuwiki-translate/lang_update_271

Translation update (fr)
Merge pull request #671 from dokuwiki-translate/lang_update_273

Translation update (fr)
Merge pull request #672 from dokuwiki-translate/lang_update_274

Translation update (ka)
Merge pull request #618 from splitbrain/cache_and_cachetime

Fix longstanding issue with cache class & cachetime setting
update deprecation stuff for dw_qearch
add defaults to phpdocs of search universal
no fancy quotes in user manager import description
Merge pull request #675 from splitbrain/depr_dwqsearch

Deprecated dwqsearch updated, no fancy quotes, some phpdocs
Release preparation
translation update
Merge pull request #680 from dokuwiki-translate/lang_update_3

Translation update (de)
translation update
Merge pull request #682 from dokuwiki-translate/lang_update_4

Translation update (ka)
Authldap: implement change password in modifyUser