Under a second to start and test against a real MongoDB instace in Docker:
$ go test -v camlistore.org/pkg/sorted/mongo
=== RUN TestMongoKV
--- PASS: TestMongoKV (0.79 seconds)
PASS
ok camlistore.org/pkg/sorted/mongo 0.791s
Test is skipped in short mode, or if docker isn't available.
Change-Id: I6f3acc96357cf9c50054b3df6727661c9329e6bf