Bump binary version to 0.21.0

I am Groot CI · I am Groot CI · commit adc6df6fbce3 · 2017-07-06T16:47:30.000Z
diff --git a/version.go b/version.go
@@ -1,3 +1,3 @@
 package main
 
-const version = "0.20.1"
+const version = "0.21.0"
