Deprecate older API wrappers and calls

Those old classes have now non-static pendants and can be deprecated IMHO.
Fix case-sensitivity
Don't disclose relative directory path for single shared files of user

The "dir" key is used within the public sharing template to indicate in which directory the user currently is when sharing a directory with subdirectories. This is needed by the JS scripts.

However, when not accessing a directory then "dir" was set to the relative path of the file (from the user's home directory), meaning that for every public shared file the sharee can see the path.
(For example if you share the file "foo.txt" from "finances/topsecret/" the sharee would still see the path "finances/topsecret/" from the shared HTML template)

This is not the excpected behaviour and can be considered a privacy problem, this patch addresses this by setting "dir" to an empty key.
Remove unused variable and make Scrutinizer happy.
add postfix

add postfix
replace all static calls to OC_Config and OC_Preferences to calls to OCP\IConfig
replace double quotes with single quotes
Remove exec() call with invalid name on windows

Currently running unit tests prints the following message 3 times:
The command "command" is misspelt or could not be found.
Instead of trying this, we just skip this now.
Deduplicate function by moving it to the OC_Helper
Simplify the binary finding code in the movie preview class
Check for XMLWriter class

This is not installed by default in all cases and will break the DAV features of ownCloud. Lot's of reports such as https://github.com/owncloud/ios-issues/issues/167#issuecomment-63798507
cleanup languages. closes #11274
drop dependency of some commands on old config object
Clean up the test data in tearDownAfterClass()

The result of the listener should then be empty and can be removed
Remove testcleanuplistener.php
Merge pull request #12325 from owncloud/removeunneccessarylang

cleanup languages. closes #11274
Merge pull request #12299 from owncloud/clean-lib-base-config

replace all static calls to OC_Config and OC_Preferences to calls to OCP...
Fix file upload to ext storage when recovery key is enabled

Fixes an issue when uploading files to external storage when recovery
keys are enabled

The Util class only works with real users, so instantiating it with the
virtual recovery key user or public key user can cause issues.
Merge pull request #12321 from owncloud/checkForXMLWriter

Check for XMLWriter class
Merge pull request #12330 from owncloud/jenkins-eat-that

drop dependency of some commands on old config object