docs: Fix missing generated docs (#1754)

docs/nav-methods.md

@@ -0,0 +1,19 @@
+- Core
+	- [m](hyperscript.md)
+	- [m.render](render.md)
+	- [m.mount](mount.md)
+	- [m.route](route.md)
+	- [m.request](request.md)
+	- [m.jsonp](jsonp.md)
+	- [m.parseQueryString](parseQueryString.md)
+	- [m.buildQueryString](buildQueryString.md)
+	- [m.withAttr](withAttr.md)
+	- [m.trust](trust.md)
+	- [m.fragment](fragment.md)
+	- [m.redraw](redraw.md)
+	- [m.version](version.md)
+	- [Promise](promise.md)
+- Optional
+	- [Stream](stream.md)
+- Tooling
+	- [Ospec](https://github.com/lhorie/mithril.js/blob/rewrite/ospec)