* Set allowed OIDs to any value when generaing a CA.
Also, allow utf-8 in addition to utf8 as the OID type specifier, and
allow `*` to specify any OID of a supported type.
* Update PKI docs
* Update PKI to natively use time.Duration
Among other things this now means PKI will output durations in seconds
like other backends, instead of as Go strings.
* Add a warning when refusing to blow away an existing root instead of just returning success
* Fix another issue found while debugging this...
The reason it wasn't caught on tests in the first place is that the ttl
and max ttl were only being compared if in addition to a provided csr, a
role was also provided. This was because the check was in the role !=
nil block instead of outside of it. This has been fixed, which made the
problem occur in all sign-verbatim cases and the changes in this PR have
now verified the fix.