Remove unsafe "unset" defaults

Remove unsafe "unset" defaults

All of our sensitive parameters are defaulted to easily predictable
values, which is very bad from a security perspective because we don't
force clients to make sane choices thus risk deploying with the
predictable default values.  tripleoclient supports generating random
values for all of these, so remove the defaults, for non-tripleoclient
usage we can create a developer-only environment with defaults.

Related-Bug: #1516027
Change-Id: Ia0cf3b7e2de1aa42cf179cba195fb7770a1fc21c
Depends-On: Ifb34b43fdedc55ad220df358c3ccc31e3c2e7c14