ref #10392

- the file/folder's permission is now stored in the file cache
- BackGroundWatcher has been removed - this has meanwhile be replaced by occ files:scan which can be executed in a cron jobs
- increase version to trigger database migration

This includes all mountpoints except the Shared one in
the used space calculation.

Added unit tests for ext storage inclusion in quota calculation

# The first commit's message is:

adding tests for long paths
increment path field in database up to 4000 (maximum for Oracle - otherwise we could use php's 4096)
increment version to trigger database migration
adding unit test for too long path

# This is the 2nd commit message:

fix too long path

* test case added to avoid adding them later

Make sure to correctly check for string emptiness when the passed path
is "0".

after being uploaded in .part files

Fix #8131

The write-hook also is triggered for created files

Fix #8131