Update scamper to 20130824.  Scamper's homepage (and code) has shifted.
PR pkg/48156

* add a sc_warts2json utility program that prints out JSON renderings
  of trace, ping, and dealias objects in scamper warts files.  this is
  useful when developing simple analysis programs in perl.  the
  initial implementation of JSON output for ping and trace was
  supplied by Internap.  Thanks a lot Internap!

* add a sc_speedtrap utility program that resolves a set of IPv6
  interfaces for aliases (which interfaces belong to the same router).
  documented in sc_speedtrap(1) man page.
  http://www.caida.org/~mjl/pubs/speedtrap.pdf

* add a sc_ipiddump utility program that prints out all IPIDs received
  in ping and dealias objects.  documented in sc_ipiddump(1) man page.
  in ping and dealias objects.  documented in sc_ipiddump(1) man page.

in scamper:
* output json objects with -O json
* add -O debugfileappend, causing the debugfile to be appended to
  rather than truncated
* do not output debugging information to stderr if NDEBUG was
  specified
* drain fds that are not used by any measurement but have not been
  closed yet
* improve the use of poll()
* allow a control socket client to specify its mixing priority
* correctly interpret the neighbour discovery cache sysctl on MacOS.
* fix build on MacOS systems without IPFW.
* fixes prompted by clang static analysis.
* fixes prompted by clang static analysis.

in sc_analysis_dump:
* improvements to the comment header printed automatically at the start
* add -M option to print out MPLS headers in ICMP extensions.
* add -Q option to print out Quoted IP TTL
* add -T option to print out the IP TTL of the response packet

in scamper-ping
* implement stats function so that the stats printed are not junk
* add an -M <mtu> option which causes scamper to send a PTB in
  response to a packet larger than the given size.
* add a -P icmp-time option which causes ping to send ICMP timestamp
  requests.
  requests.

in scamper-sting:
* various improvements in the hole filling phase.
* add -U <userid>

in scamper-dealias:
* implement IPv6 support for Ally and RadarGun which is induced by
  sending ICMP echo packets larger than a given pseudo MTU size
  (causing a responses to be fragmented and thus an ID field revealed.
* implement IPv6 support for Mercator
* be more strict in declaring two interfaces to be aliases: infer
  the byte ordering by determining if the shortest distance in a
  sequence of ID values is in byte-swapped or not, and then using
  that byte ordering mode.
scamper update.