Merge pull request #9754 from owncloud/enc_support_aes_256

apps/files_encryption/ajax/changeRecoveryPassword.php

apps/files_encryption/ajax/updatePrivateKeyPassword.php

apps/files_encryption/hooks/hooks.php

apps/files_encryption/lib/crypt.php

apps/files_encryption/lib/exceptions.php

apps/files_encryption/lib/helper.php

apps/files_encryption/lib/keymanager.php

apps/files_encryption/lib/session.php

apps/files_encryption/lib/stream.php

apps/files_encryption/lib/util.php

apps/files_encryption/tests/crypt.php

apps/files_encryption/tests/keymanager.php

apps/files_encryption/tests/share.php

apps/files_encryption/tests/util.php

config/config.sample.php