devel: Removed still unimplemented app
devel: Removed still unimplemented app

Removed from this branch to avoid build errors until it is actually
added

SebastianNiemann/Mantella,SebastianNiemann/Mantella,Mantella/Mantella,Mantella/Mantella,SebastianNiemann/Mantella,Mantella/Mantella