Merge pull request rust-lang#2316 from szabgab/patch-1

Update book.toml fix the authors field

Author: JohnTitor

src/doc/rustc-dev-guide/book.toml

@@ -1,6 +1,6 @@
 [book]
 title = "Rust Compiler Development Guide"
-author = "The Rust Project Developers"
+authors = ["The Rust Project Developers"]
 description = "A guide to developing the Rust compiler (rustc)"
 
 [build]