Allow read-only configuration

Workaround required for IIS setups running ownCloud to prevent dataloss.

Long-term solution would be to move some configuration settings to the database
new folder structure for keys
all keys are now in files_encryption/key/path_to_file/filename/
share keys are named: user.shareKey
file key is named: fileKey
harmonize copyright notice
change private/public key names for consistency reasons
Check if files are deletable before trying to delete them
Dont show the delete button for selected files if one of the selected files is not deletable
Add js unit test
remove border from user menu, adjust to apps menu
include lock files of bower to be able to use "bower install"
move jstz to bower management
Added error check to lib/private/image.php

This checks that imagecreatetruecolor actually creates an image, rather than returning FALSE.
Without this check, subsequent loop might create billions of ERROR-level log messages.

Signed-off-by: Byron Marohn <combustible@live.com>
Use \OCP\ILogger
Merge pull request #12419 from owncloud/read-only-config

Allow read-only configuration
Implement a logger to log to error_log
Merge pull request #12310 from kampka/master

Implement a logger to log to error_log
Better manage the output when running autotest.cmd
Allow passing a test file just like in autotest.sh
Allow overwriting DATADIR completly so ramdisk can be used
Restore the development config after running the tests
Clear statcache before getting the mtime from local storage backends