The creator tool takes -n (namespace) option for table name prefixes.

Since HBase has no notion of database schema, we just opt to stick the
literal value of the option in front of every table name.

The rspec schema macro is also namespace-aware, so that tests can
sandbox their tables away from any possible production equivalents.
When the schema block accepts a hash to populate tool options, that
hash is taken to be the entire tool options hash, instead of just the
'jars' option.