* Added a sanity check to rddbmgr(8) to prevent reverting from an
unknown schema.
* Added a sanity check to rddbmgr(8) to prevent inadvertent
reversion to an implied schema.
* Stubbed out rddbmgr(8).
* Implemented the '--create' command in rddbmgr(8).
* Fixed a bug in 'RDStation::create()' that generated corrupt records
in the 'AUDIO_INPUT' and 'AUDIO_OUTPUTS' tables when creating a
new host with no exemplar.