With the introduction of the grouping mechanisms of the
caching framework and the sensitivity of the system
caches group, the re-ordering and re-naming of cache
menu entries is necessary to ensure that admins and
editors use the caching mechanisms right.

Therefore there are new labels as well as "Clear all caches"
below "Clear page content" as it has a higher impact on
the system. The option to clear the Configuration Cache
/ System Caches is now disabled by default, even for
admins. It is active when the TSconfig option
options.clearCache.system = 1 is set or if the system is in
development context. This avoids slow page rendering
after clearing the system caches.

A new title attribute is added to explain the menu items
when hovering.

Resolves: #55119
Releases: 6.2
Change-Id: Ifd6026279a890b743c6c3cda09def19f9b7d59b7
Reviewed-on: https://review.typo3.org/26912
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Marcin S?gol
Tested-by: Marcin S?gol
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters

The current TYPO3 Core includes different types of caches. There are
system-related caches (class loading cache, configuration cache,
l10n_cache, extbase_object, extbase_reflection etc.) and
frontend-related caches (chash cache, page cache, page section
cache).

The patch introduces the possibility to group caches. The core uses
two groups "pages" with all page-related caches, and "system" that
is used for compile-time caches and configuration caches.

The new API is now used to be more flexible inside DataHandler
clear_cacheCmd without having hooks, as the Cache Manager is used
to clear all caches inside one hook.

!!! The "Clear all caches" command does not flush caches for
system-related caches anymore. Only "Clear Configuration Cache" or
inside the install tool in the backend removes all the system caches.

A new userTSconfig option is used to non-admins to be allowed to
clear the system caches.

Resolves: #54991
Releases: 6.2
Change-Id: I...

The following changes to system categories should be mentioned
in NEWS.md:

* activation by default on pages and tt_content tables
* new menu types for categories-based menus

Resolves: #54368
Releases: 6.2
Change-Id: I1ca95ea6354f52a68bd31cf284d6a103563190a4
Reviewed-on: https://review.typo3.org/26362
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel

* Added README.md (which was formerly part of the individual
  distributions)
* Transformed the text into markdown for nice visualisation i.e.
  on Github
* Rewritten the installation steps
* Rewritten the system requirements

Releases: 6.2
Resolves: #53745
Change-Id: I293bde1a046e9f7c712d5d8d9cc13138a303efc2
Reviewed-on: https://review.typo3.org/25490
Reviewed-by: Michael Stucki
Tested-by: Michael Stucki
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Ernesto Baschny
Tested-by: Ernesto Baschny