Fix bug so that the segment separator of left middle has the right color
Fix bug so that the segment separator of left middle has the right color

In short: the current background color was the unfiltered color and is
used to print the next segment separator. If the user set a color like
"purple3" that would result in a white segment separator as Terminal
Emulators do not understand the color "purple3".

dritter/powerlevel9k,bhilburn/powerlevel9k,bhilburn/powerlevel9k,dritter/powerlevel9k