pt_util: Initialise empty database correctly

pt_util: Initialise empty database correctly

Commit dc8f18d6f5003712bc9ef989363137a84953df07 broke pt_util's
initialisation of empty databases. This is because Initdb was changed
to call Initdb_check through the ubik_CheckCache wrapper. However, that
wrapper was defined as a no-op in pt_util's ubik-shim.

Modify pt_util's ubik_CheckCache so that it always calls into the
wrapper routine - this mimics the old behaviour.

Add a trival test for pt_util - check that we can build the database,
using the example from the manpage, and then that the built database
matches what we expect.

Change-Id: I41aa9f6a531662230ed625cc3b1307016ef4107f
Reviewed-on: http://gerrit.openafs.org/4211
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>