[readme] Add a link to the roadmap.
Fixes
@@ -78,6 +78,9 @@ features:
* **Competition:** provides [leaderboards](#leaderboards) for you to submit your
results.
+For a glimpse of what's to come, check out [our
+roadmap](https://github.com/facebookresearch/CompilerGym/projects/1).
+
# Getting Started
Starting with CompilerGym is simple. If you not already familiar with the gym
