minor, track state in a re-entrant fashion in xmas DSO

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, provide strctl routine for xmas DSO

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, track state in a re-entrant fashion in new-year DSO

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, provide strctl routine for new-year DSO

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'dso/general' into next

* dso/general:
  minor, provide strctl routine for new-year DSO
  minor, track state in a re-entrant fashion in new-year DSO
  minor, provide strctl routine for xmas DSO
  minor, track state in a re-entrant fashion in xmas DSO
Merge branch 'next'

* next:
  minor, provide strctl routine for new-year DSO
  minor, track state in a re-entrant fashion in new-year DSO
  minor, provide strctl routine for xmas DSO
  minor, track state in a re-entrant fashion in xmas DSO
  minor, follow implicit cloning changes in builders.c
  minor, silently clone stream passed in to echs_select() builder (and unclone upon echs_free_select())
  hygiene, instead of opening the easter DSO twice, use clone_echs_stream() primitive in de holiday list
  minor, provide generic controller function in easter DSO
  minor, build libechse with strctl functionality
  minor, provide generic stream (and filter) controlling through strctl.[ch]
  minor, use echs_select() builder for easter and ascension in de holidays DSO
  minor, track state in a re-entrant fashion in easter DSO
  minor, make echs_free_select() return the stream that has been selected over
  minor, provide select builder to obtain single events from an underlying stream
  minor, provide re-entrant version of echs_mux()
  fix, actually assign the number of streams to echs_mux_clo
  minor, add 1 May (Labour day) to de's holidays
  minor, provide echs_mux() builder that does muxing like echse(1) does
  minor, import example stream for germany as de.la
  chore, create beef directory for example streams