[krbdev.mit.edu #2919] Default ticket lifetime changed with 1.4

[Sam Hartman via RT]

Hi.  It actually turns out that default_lifetime is respected by 1.4
but was not respected by previous versions of Kerberos at all.

OUr default_lifetime handling is the same as Heimdal's.  Some sites
were distributing configuration files that assumed default_lifetime
was in minutes.  We've never shipped code that worked that way.