Merge branch 'next'

* next: (26 commits)
  fix, PEBKAC, close sockets first, then destroy event loop
  fix, always initialise lstn fds
  fix, PEBKAC, don't stop a prepare watcher that hasn't been started
  debug, PEBKAC, output variables that actually exist
  fix, PEBKAC, log to umpf_logout (mismerge from gandalf's nifty.h)
  fix, PEBKAC, spell lua for PKG_CHECK_MODULES macro so that the Makefile can find it
  minor, convert be-sql from unserding syslogging to umpf syslogging
  minor, kick unserding_{CFLAGS,LIBS} from the umpfd build specs
  major, convert dso-umpf.c to standalone daemon
  chore, mention ud-sockaddr.h as noinst_HEADERS so it goes into the dist
  chore, outsource sockaddr union guts and goodies into ud-sockaddr.h
  chore, add gq.[ch] to EXTRA_umpfd_SOURCES
  minor, import gq.c and gq.h
  minor, merge gandalf's nifty.h with umpf's
  minor, import stuff needed for standalone mode
  chore, formally rename dso-umpf to umpfd.c in preparation ...
  chore, do not hardcode CFLAGS, instead let the compiler macros find out what's best
  chore, kick nested message initialisation from c.ac
  chore, update sxe-aux.m4
  minor, import sxe-linker.m4 and sxe-libtool.m4 and adapt c.ac to using them instead of LT_INIT directly
  ...