mrv2 v0.6.2

This is a minor release to fix some subtle bugs.

v0.6.2

• Fixed the Media Info Panel crashing on start-up when the panel was open and
  the media was an OpenEXR with multiple layers.
• Made timeline cursor be white for easier reading on the eyes.
• Fixed timeline cursor not ending in last frame when dealing with sequences.
• Fixed Auto Refit Image preference working only after a restart of the
  application.
• Fixed Media Info Panel showing up with scrollbars when mrv2 was started
  command-line and with a movie.
• Fixed Save Movie or Sequence and Save PDF Document allowing to be selected
  even when no movie was loaded.
• Fixed mrv2's File requester saving always overwriting the file that was
  selected instead of using the filename in the filename input widget.
• Added a ffmpeg_windows_gpl.sh script to compile a GPL version of FFmpeg with
  libx264 and libvpx suport on Windows.
• Made mrv2's GL window swallow Left Alt key presses when pressed alone to
  avoid Windows' taking over the Window.