files have really old descriptors for the authdirservers, so we're
asking them in the new format because they're too old.

now we actually compare the version to a cutoff version, and act
appropriately.

also take this chance to use only >=0.0.8 servers for dns resolves,
because of the recent bugs. we'll bump to >=0.0.9pre1 once there are
some servers running that.


svn:r2380