update versions for 0.28.0-rc1
diff --git a/VERSION.txt b/VERSION.txt
index c55fc9b..697f087 100644
--- a/VERSION.txt
+++ b/VERSION.txt
@@ -1 +1 @@
-0.28.0-SNAPSHOT
+0.28.0
diff --git a/python/docs/conf.py b/python/docs/conf.py
index 26de3b5..25f6e8a 100644
--- a/python/docs/conf.py
+++ b/python/docs/conf.py
@@ -50,7 +50,7 @@
 # The short X.Y version.
 version = '0.28.0'
 # The full version, including alpha/beta/rc tags.
-release = '0.28.0-SNAPSHOT'
+release = '0.28.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.