RFC 2857 is the 2020 roadmap

Author: Manishearth

text/0000-roadmap-2020.md renamed to text/2857-roadmap-2020.md

@@ -1,9 +1,9 @@
-# Rust 2020 Roadmap RFC Draft
+# Rust 2020 Roadmap
 
 - Feature Name: N/A
 - Start Date: 2020-01-22
-- RFC PR: [rust-lang/rfcs#0000](https://github.com/rust-lang/rfcs/pull/0000)
-- Rust Issue: [rust-lang/rust#0000](https://github.com/rust-lang/rust/issues/0000)
+- RFC PR: [rust-lang/rfcs#2857](https://github.com/rust-lang/rfcs/pull/2857)
+- Rust Issue: N/A
 
 # Summary
 [summary]: #summary