all: release v0.26.0 (#517)

CHANGES.md

diff --git a/CHANGES.md b/CHANGES.md
index c2e3e0c..98831cd 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,17 @@
+# v0.26.0
+
+## Changes
+
+- idtoken:
+  - Populate Claims map.
+- transport/http:
+  - Update default HTTP transport settings to use a larger value for
+    MaxIdleConnsPerHost. This improves performance in the storage client.
+- Various updates to autogenerated clients.
+
+_Please note:_ the release version is not indicative of an individual client's
+stability or version.
+
 # v0.25.0
 
 ## Announcements

internal/version/version.go

diff --git a/internal/version/version.go b/internal/version/version.go
index b24a5da..5a89da7 100644
--- a/internal/version/version.go
+++ b/internal/version/version.go
@@ -10,4 +10,4 @@
 
 // Repo is the current version of the client libraries in this
 // repo. It should be a date in YYYYMMDD format.
-const Repo = "20200518"
+const Repo = "20200601"