Problems uncovered in getting a simple stored procedure to call the key-value store

* Manifest was being read via `ClassLoader`, which looks in parent first. I think the parent became not-null to support Direct, but in any case there's a better way to do it.
* SQLJJar descriptor format usually has newlines, but regexp has `.*`.
* A Java routine with a `byte[]` argument wants a byte array input, not a single byte value output.
* Make `Transaction` public on transaction state so you can get it out for use with directory layer or something.