#4 execute() support

[Shaper super-script]

Hey, why don't you do a support for an execute()-like statement where we can run external programs upon 'commit', 'release' or 'expiry' events like isc dhcp 3.1.x?

This is very useful and in isc dhcp (which is only for ipv4) it works like this:

on commit {
if (execute ("/path/to/some/command","parameter1","parameter2",...,"parameterN")) {
log ("executed command sucessfully");
} else {
log ("problem executing command");
};
};

on release {
if ( execute (...) )...
}

on expiry {
if (execute (something like release procedures) ) ...
}

This would be a great functionality to the project, and will make possible building firewall rules as IPs are associated to clients, and even many many other things.

p.s.: I got a patch to isc dhcp 3.0.5 with little fixes from the original patch from Mattias, let me know if it would be of any use for this project's developers.