* lctl set_route <nid> <up/down> enables or disables particular portals

  routers (i.e. gateways) without forgetting network topology
  (i.e. adding/deleting routes).

* Socknal and qswnal automatically notify their local router and make an
  upcall when they detect peer death.

* portals router load balances over equivalent routes

* ENETUNREACH returned when a NAL thinks the router isn't loaded.

* Improved socknal network failure detection.

* /proc/sys/socknal/* interface

  - timeout is the socknal I/O timeout (50 by default) in seconds .

  - eager_ack is a boolean (set by default) that enables setting
    TCP_QUICKACK after every incoming message to ensure peer zero-copy
    sends complete quickly.

  - zero_copy is the size (2k by default) in bytes, below which message
    fragments are copied into a socket, rather than using zero-copy sends.
    Setting this above PAGE_SIZE will disable zero copy.

* Socknal autoconnect option to create all peer connections eagerly or not.
  If more than one autoconnect reaches the same peer NID, with the eager
  option (this was the previous default), all connections will be made when
  one is required, otherwise only one at a time will be attempted (the new
  default).  NB socknal still load balances over all established
  connections.

* Generalised portals upcall to "cmd <action> [params]".  Current upcalls
  are...

  - upcall LBUG file fn line

  - upcall ROUTER_NOTIFY <nal> <nid> <timestamp> up|down
    where <nal> is the kernel NAL number (defined in <linux/kp30.h>)
          <nid> is the peer's NID in 0xhex
          <timestamp> is seconds since 1/1/1970

* Added 'lctl --net' option, to make 1-line network lctl commands easy.

* Added Light-weight event tracing.