Fix README link.

Author: jq-rs

Cargo.toml

@@ -8,7 +8,7 @@ description = "Mles WebProxy - an Mles WebSocket proxy and a static WWW-server b
 license = "MPL-2.0"
 repository = "https://github.com/jq-rs/mles-webproxy"
 documentation = "https://mles.io"
-readme = "../README.md"
+readme = "README.md"
 categories = ["network-programming"]
 keywords = ["websocket", "proxy", "www", "server", "mles"]