Merge branch 'public'

* public:
  pathmtu: New program for determining the MTU to a host.
  server/admin: New ALGS command.
  Build: Explicitly link against mLib or catacomb.
  tripe-keys: Add a subcommand to print the correct tunnel MTU.
  client/tripectl.c: Fix format string bug in tripectl.
  init/Makefile.am: Switch install-hook to install-data-hook.
  configure.ac: Use AM_PATH_GLIB_2_0.