SyncPlayer 1.6.11 - offset indicator, self-sufficient crop window

Added

• The alignment offset is shown in the status readout, so it can be read at a glance and
  typed back in next session.
• Capture frame and Grab screen buttons inside the visual crop window, so a frame can be
  fetched from within it. Grab screen shows the video fullscreen, reads the frame off the
  screen and restores the window afterwards.
• The crop window opens with a placeholder instead of refusing when the first capture
  fails, which keeps those two buttons reachable, and it reports which route produced the
  frame on screen.
• HDR and Dolby Vision handling: the transfer is detected and the capture is tone-mapped
  for it, with the software route first; a frame that still comes back essentially black
  is lifted so the picture can be seen.

Fixed

• The crop window could not display a frame fetched by its own buttons: the reload scaled
  an attribute that does not exist.