Update adapter.php

Modified insertIfNotExist() to support NULL values
add unit test
Also update sqliteadapter
Fix use Sharing Api with calendar

Without this fix it logs this error:
Undefined index: itemSourceName at /opt/local/apache2/htdocs/oc7/core/ajax/share.php#44
I think the itemSourceName is only used with sharing files!
fix orientation in image-backend, not in preview system itself
Remove special case for css in OC.filePath
Fixed file list sorting

Now using a natural sort algorithm that is more consistent between JS
and PHP (although not perfect in some corner cases)

- added OC.Util.naturalSortComparator that uses the same algo that was
  used for the user list
- changed user list and files list to use OC.Util.naturalSortComparator
- removed toLowerCase() and changed the comparator to use
  String.localeCompare()
- added unit tests
- added OC_NaturalSort that is used by OCP\Util::naturalSortCompare()
Fixed sort algo for additional cases
improve logo flexibility to fix wide custom logo alignment, fix #9339
Use Doctrine Platform to generate SQL query for table truncation.
Refactor internal session to write directly to $_SESSION
Libreoffice config folder needs to be set

In order to avoid conflicts between multiple instances installed on one server, it's required to define a LibreOffice configuration folder per instance.

Just like with my PR for the documents app (https://github.com/owncloud/documents/pull/353), I propose to use /tmp/owncloud-instanceid
Update AWS sdk to 2.6.15
Fix failing AmazonS3::touch on updated aws sdk
Initialize an event source when we start using it, not in the constructor
Add event source to the public api
Use the public api to get event sources
env:UserInstallation was already there in master

My changes were made against stable7 and I merged them to the file in master, so this version is now the properly merged file for master.
I'm just adding `owncloud-<instanceid>` to the path where temp files are stored.
Added acceptance tests for enabling apps

This tests whether a user can see navigation entries after enabling
apps. This includes the app's group restriction.

This currently expects that a group "group1" exists until we have code
to auto-generate groups.

This commit also provides a utility function
Page.multiselectSetSelection() to make it possible to select entries
inside a multiselect.
Use correct language package so the subject is correctly translated

Fix #10847