triton: improved epoll events handling
radius: release auth request immediatly after get responce

There is no need to keep auth request structure in memory during whole session life time.
It wastes memory and file descriptors
radius: close socket after receiving accounting reply
pppoe: introduced called-sid option.

This new option will control how to represent Called-Station-ID.
Its value maybe ifname,mac or ifname:mac.
By default mac is used to keep compatibility with old versions.
Also old option ifname-in-sid is removed from documentation, but is still supported for compatibility.
radius: add support for Nas-Port-Id attribute (interface name)
radius: use NAS-Port-Id in Access-Accept for interface renaming
ippool: introduced shuffle option

By default list of IP address is serial at startup.
This option shuffles initial IP list so it becomes more random.
radius: introduced weight and backup per-server options

New options are applied to server option as server=...[,weight=x][,backup]
Weight is used for multi-server configurations (larger weight takes more users).
Backup is used to mark backup server f.e. server which will be used only if all other servers are failed.
triton: close file descriptors immediately in triton_unregister_handler
Merge branch 'master' of git://git.code.sf.net/p/accel-ppp/code