Add link to rustdoc roadmap

Author: Manishearth

text/0000-roadmap-2019.md

@@ -226,8 +226,8 @@ They'll be working to fulfill these functions this year, along with looking
 for ways to improve their internal processes.
 
 Individual devtools subteams may be coming up with their own roadmaps, you
-can see the one of Cargo above, and the IDE team
-[here](https://github.com/rust-dev-tools/dev-tools-team/blob/master/roadmaps/ides-and-editors-2019.md).
+can see the one of Cargo above, the IDE team
+[here](https://github.com/rust-dev-tools/dev-tools-team/blob/master/roadmaps/ides-and-editors-2019.md), and the rustdoc team [here](https://github.com/rust-dev-tools/dev-tools-team/blob/master/roadmaps/rustdoc-2019.md).
 
 ## Documentation