Function gsl_sys::gsl_movstat_median

pub unsafe extern "C" fn gsl_movstat_median(
    endtype: gsl_movstat_end_t, 
    x: *const gsl_vector, 
    y: *mut gsl_vector, 
    w: *mut gsl_movstat_workspace
) -> c_int

This is supported on crate feature v2_5 only.