[BUGFIX] Collapse icon for accordion not centered in Install Tool

Resolves: #60192
Releases: 6.3,6.2
Change-Id: I4bacce041ca3be3dce4cae1a7407ab3fdf301ff0
Reviewed-on: https://review.typo3.org/31524
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Sascha Egerer
Tested-by: Sascha Egerer
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
[BUGFIX] Fix page module styling in Languages view

Change in height of table header row for Languages view.

Resolves: #56714
Releases: 6.3, 6.2
Change-Id: Ic6bab8a99695798ecfc115209aec41e241870925
Reviewed-on: https://review.typo3.org/31498
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
[TASK] Clarify exception message for addPlugin()

Add verbosity to the exception message to make it
more clear what is going wrong.

Releases: 6.2, 6.3
Resolves: #60225
Change-Id: I7bb4a16ff94d05b8b97633383d42c61aa600b1cf
Reviewed-on: https://review.typo3.org/31556
Reviewed-by: Christian Kuhn
Reviewed-by: Markus Klein
Reviewed-by: Wouter Wolters
Tested-by: Christian Kuhn
Reviewed-by: Alexander Opitz
Tested-by: Alexander Opitz
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel
[BUGFIX] Use PATH_site in cache identifier for package cache

The package cache writes paths to extension directories
(TYPO3_LOADED_EXT) into the cache.

This will result in wrong caches when the same
TYPO3 instance is called from a different absolute
directory e.g. from a different mount or symlink.

To avoid this, the cache identifier now includes
PATH_site which is the current absolute path
of the TYPO3 instance.

Additionally we now only include the modification
time of the package states file instead of the
md5 of the complete content into account, which should
be much faster and also enough.

Resolves: #58288
Releases: 6.2, 6.3
Change-Id: I7c8de41c608beab282f2b8bbeab39f257a9a6a6f
Reviewed-on: https://review.typo3.org/31565
Reviewed-by: Markus Klein
Tested-by: Markus Klein
Reviewed-by: Stefan Neufeind
Tested-by: Stefan Neufeind