Upgrade from 3.1.0 to 4.1.1

[sthaug at nethelp.no]

> where can i found info on how to compile with USE_SOCKETS and how can
> i use this feature. i only need to run multiple DHCP instances on
> different ports using the same IP

Here:

https://lists.isc.org/pipermail/dhcp-users/2009-August/009667.html

is the recipe I used to compile with USE_SOCKETS on FreeBSD. Note:

- Step 3 in that recipe is no longer needed with 4.1.1 release version.

- If your environment doesn't use BPF (e.g. Linux, Solaris) then you
don't need the USE_BPF_HWADDR define.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no