add back page about auto reloading

For folks finding this page via search engines, there was still info
regarding listenfd and systemfd which is no longer recommended.

content/docs/autoreload.md

@@ -0,0 +1,22 @@
+---
+title: Autoreloading
+menu: docs_patterns
+weight: 1000
+---
+
+# Auto-Reloading Development Server
+
+During development it can be very handy to have cargo automatically recompile the code on change.
+This can be accomplished very easily by using [cargo-watch][cargowatch].
+
+```sh
+cargo watch -x 'run --bin app'
+```
+
+## Historical Note
+
+An old version of this page recommended using a combination of systemfd and listenfd, but this has
+many gotchas and was difficult to integrate properly, especially when part of a broader development
+workflow. We consider [`cargo-watch`] to be sufficient for auto-reloading purposes.
+
+[`cargo-watch`]: https://github.com/passcod/cargo-watch