Be explicit about linux package names for those not familiar with
the platform. Also more explicit about steps such as editing file,
and testing the daemon.
Remove leading whitespace from commented-out config examples.
Set default parallel DNS back to 10, and suggest override of 100 in
config file. Enforce skipped DNS for autoconf IPs if unset (this is
a consequence of the way Dancer merges the two files - top level
config cannot be in both files).