Release version 0.4.0

.bumpversion.cfg

 [bumpversion]
-current_version = 0.4.0.dev
+current_version = 0.4.0
 parse = (?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)(\.(?P<release>[a-z0-9]+))?
 serialize = 
 	{major}.{minor}.{patch}.{release}
@@ -11,9 +11,6 @@ values =
 	dev
 	unused
 
-# Files in which to bump versions are configured below.
-# This can be changed to suit your project.
-# This example works with python setup.cfg file.
 [bumpversion:file:setup.cfg]
 search = version = {current_version}
 replace = version = {new_version}

setup.cfg

@@ -3,7 +3,7 @@
 [metadata]
 name = differential_privacy
 # Do not modify version manually. Use bump2version instead.
-version = 0.4.0.dev
+version = 0.4.0
 author = Wikimedia Foundation Privacy team
 description = Spark pipelines for differential privacy
 long_description = file: README.md