Update version number of package:func.

This package has been stable and widely used for a while now so there
was no need for a version number under 1.0

BUG=
R=djmurphy@google.com, zra@google.com

Review-Url: https://codereview.chromium.org/2819903003 .
diff --git a/pubspec.yaml b/pubspec.yaml
index 67ea524..965993c 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: func
-version: 0.1.1
+version: 1.0.0
 description: >
   Typedefs defining commonly used function types to make it simpler to
   define members that return specific function types.