Merge pull request #23 from dart-lang/pq-patch-1

Update SDK constraint to be 2.0.0 dev friendly.
diff --git a/pubspec.yaml b/pubspec.yaml
index af9075d..05ccd97 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -5,7 +5,7 @@
 homepage: https://github.com/dart-lang/cli_util
 
 environment:
-  sdk: '>=1.11.0 <2.0.0'
+  sdk: '>=1.11.0 <2.0.0-dev.infinity'
 
 dependencies:
   path: '>=1.0.0 <2.0.0'