More flakes work

Removed old git submodules
Started adding Windows cross compilation support

nl-sys/build.rs

@@ -22,7 +22,8 @@ fn main() -> std::io::Result<()> {
 
     let mut options = CopyOptions::new();
     options.copy_inside = true;
-    copy(std::env!("SPARSE_BUILD_LIBNL"), &libnl_src, &options);
+    options.skip_exist = true;
+    copy(std::env!("SPARSE_BUILD_LIBNL"), &libnl_src, &options).expect("could not copy nl");
 
     let dst = autotools::Config::new(libnl_src).reconf("-vi").build();