Function install_serial_feral_backend 

pub fn install_serial_feral_backend(app: &mut IpoptApplication)

Install an inner-serial FERAL backend on app, honoring any feral_* options already set (read the options before calling this if configure sets them — i.e. set options first, then call this). The parallel = off toggle is per-backend; concurrent solves on other threads are unaffected.