Add initial code for sadis-server.

Change-Id: Iaa8d6ddf888c04abc8eee5933c0c7401c0094394
diff --git a/vendor/github.com/kelseyhightower/envconfig/env_os.go b/vendor/github.com/kelseyhightower/envconfig/env_os.go
new file mode 100644
index 0000000..a6a014a
--- /dev/null
+++ b/vendor/github.com/kelseyhightower/envconfig/env_os.go
@@ -0,0 +1,7 @@
+// +build appengine
+
+package envconfig
+
+import "os"
+
+var lookupEnv = os.LookupEnv