Cydia Eraser is all you need, get it from Cydia, backup phone, turn on wifi, run Cydia eraser, let it do its thing, phone restarts you are back to fresh install as you would of got it from day one! This will remove your jailbreak and factory restore but you can re-jailbreak.
I did it on my 9.3.3 i6S and 6 ios 8.4!