Fixed Multipartfiles only accepting a single file.

Added som standard derives on File struct, and extractors

examples/multipart_file/src/main.rs

@@ -0,0 +1,37 @@
+use axum::extract::DefaultBodyLimit;
+use lib::axum::app::AppBuilder;
+use lib::axum::extractor::MultipartFiles;
+use lib::routes;
+
+// 0 or more
+async fn with_optional_file(files: Option<MultipartFiles>) -> String {
+    format!(
+        "{:?}",
+        files.map(|files| files
+            .0
+            .into_iter()
+            .map(|file| file.filename)
+            .collect::<Vec<_>>())
+    )
+}
+
+// 1 or more files
+async fn handler(MultipartFiles(files): MultipartFiles) -> String {
+    format!(
+        "{:?} uploaded",
+        files
+            .into_iter()
+            .map(|file| file.filename)
+            .collect::<Vec<_>>()
+    )
+}
+
+#[tokio::main]
+async fn main() {
+    let route = routes!(
+        get "/" => handler,
+        get "/opt" => with_optional_file
+    )
+    .layer(DefaultBodyLimit::disable());
+    AppBuilder::new().route(route).serve().await.unwrap();
+}