What's new:
* fixed SMB mounts when no username is provided
* fixed a bug where MMAL cameras would get some V4L2 motion config options
* added `webcontrol_parms` option to enable motion HTTP API on motion 4.1 or later
* fixed content type for downloaded movie files (thanks to Mrnt)
* frame rate is now dimmed when a dialog is opened (thanks to Mrnt)
* lots of Docker improvements (thanks to kleini)