Move OC_Archive to \OC\Archive and PSR-4

PSR-4 for apps

Cleanup Files_Sharing CLASSPATH

Use correct typehint for the IProviderFactory

Move activity manager to the namespace

* Move out of legacy folder
* Move to proper namespace
* Fix calling code

* Fix code
* Fix tests

Adding repair steps for install and uninstall 

add ISession::getId() wrapper for session_id

* OC\Files\Cache\SharedScanner
* OC\Files\Cache\Shared_Cache
* OC\Files\Cache\Shared_Permissions
* OC\Files\Cache\Shared_Updater
* OC\Files\Cache\Shared_Watcher
* OCA\Files\Share\Maintainer
* OCA\Files\Share\Proxy

Merge pull request #24336 from owncloud/issue-24328-remove-password-from-exception-trace-in-dav-auth

Remove the password from the validateUserPass() method as well

Fix undefined variable $ex

Better callForAllUsers memory usage

Test an event in the far future 

Remove dead code

Add files:scan warning when NFD or incompatible encoding found

Ancient files_sharing updater code I came across.

Move lonely file from \OC\Files to PSR-4

Conflicting PR probabaly caused this

\OC\Group to PSR-4

Move non PSR-4 files from lib/private root to legacy