Fix broken link to roadmap.html (this is the only such broken link).

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MOS_MIGRATED_REVID=90443417

README.md

diff --git a/README.md b/README.md
index 212f73d..fcb3fb1 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# [Bazel](http://bazel.io) ([Alpha](http://bazel.io/docs/roadmap.html#alpha))
+# [Bazel](http://bazel.io) ([Alpha](http://bazel.io/roadmap.html#alpha))
 
 *{Fast, Correct} - Choose two*