Does someone know, where I can buy a three-row, 90° angled pin connector bar for the servo rail?
I don’t like that all the cables are directed to the top.
A horizontal alignment would be better in terms of space savings for me.
@dgrat Here is one on HobbyKing . Please note that if you intend to solder it with pins below Navio+, it will not fit.
I got mine off ebay for the same reason, did not have enough vertical space.
It looks very nice, but I do not want to resolder 45 pins 
A pity, that I was not finding a female/male 90 deg adapter.