Syncbase: Clarify if we do support non-VOM data

[aghassemi]

Currently we have tests for reading/writing non-VOM data. Problem is queries (even if a simple SELECT k, v FROM table) fails on non-VOM data since queries return VdlValue rather than bytes.

We should clarify if we want to support non-VOM bytes as that decision can effect the design of client APIs being discussed in #1083

If we do want to support non-VOM values, then we should fix queries not to fail.
If we don't want to support non-VOM bytes, we should change the Syncbase VDL to take any instead of byte to guarantee non-VOM bytes can't make it in.

My opinion is to stick with VOM as I don't think encoding bytes as VOM bytes is expensive.

@kenashcraft @asadovsky