Changes 6.9.71 -> 6.9.72:
* Sequencer: Add a "Duplicate seqblock and block"
  option to the editor seqblock popup menu.
* Mixer: Make current mixer slot color red.
* Mixer: Make the sound object ports more visible.
* Mixer: Improved sound object port graphics.
* Colors: Made it possible to configure the color of
  the current slot.
* Colors: Made the audio port color in the mixer
  configurable.
* Colors: Make it possible to configure the
  out-grayed color in the editor when a custom
  widget has keyboard focus.
* Colors: Make it possible to configure dialog
  help text color.
* Menus: Fix selecting "Show/Hide Mixer" and
  "Show/Hide Sequencer" without using shortcuts.
* Editor: Fix editing BPM. Bug introduced in 6.8.71.