- L10N now converted to string to make them work with json_encode
- Added specific error message when server doesn't allow fopen on URLs
- Fixed client side to correctly show error message in a notification
- Added OCP\JSON::encode() method to encode JSON with support for the
  OC_L10N_String values

Added new OC\Response API called setContentDispositionHeader() that
contains the needed workarounds for UTF8 and IE.

Refactored download code to use the new API.

Removed unused trashbin download file.

fixes #6108

Whenever a user creates a file or folder in the web UI, the input field
will contain a default file name, pre-selected up to the extension for
easier typing.

The purpose is mostly to prevent users creating text files without an
extension.

Fixes #6045

Whenever a file is renamed, if the extension changes, the mime type and
preview might change. This fix passes the updated info to the client
that updates it.

Fixes #6055
This contribution is MIT licensed!