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!
Remove special case for css in OC.filePath
Allow specifying the item source in unshareFromSelf().
add utf8 folder test
improve logo flexibility to fix wide custom logo alignment, fix #9339
Add unit tests for new unshareFromSelf() functionality.
Remove different URL for EE

This can now be achieved by setting `appstoreenabled` to `false` in config.php
add select2 to app specific thirdparty
replace chosen with select2 to provide ajaxified user and group selection for files_external, fixes #7499

remove minified select2 js

show avatars for users, simpler results

remove unneeded users and groups from settings template

fix css, escape user and group names
fix deletion of shares
no need to load user display names
add lookup route for displaynames
use displayname lookup route in files_external settings
Use AppFramework instead of custom controller
Add isAppstoreEnabled instead of hijacking the URL
Add support for getting the real client IP behind proxies

Fixes https://github.com/owncloud/core/issues/10624

Fix copy paste fail

Add unittest for comma separated headers

Revert 3rdparty
Add some security utilities

This adds some security utilities to core including:
- A library for basic crypto operations (e.g. to encrypt passwords)
- A better library for cryptographic actions which allows you to specify the charset
- A library for secure string comparisions

Remove .htaccess

Remove .htaccess

Fix typo

Add public API

Use timing constant comparision

Remove CBC constant

Adjust code

Remove confusing $this