Bump Bazel version to 2.0.0

Change-Id: Ie7e432dcec730f513ec73b25a3e66a9f7e5d54cc
diff --git a/.bazelversion b/.bazelversion
index 9084fa2..227cea2 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-1.1.0
+2.0.0