minor, use slots in utectx structure to keep track of iter state instead of static globals

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

* core/iter:
  minor, use slots in utectx structure to keep track of iter state instead of static globals
minor, use programmatic ute_iter() to provide matlab's ute_tick

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, take number of ticks from ute_nticks() directly in matlab's ute_nticks

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, simplify matlab handle layout again, don't store nticks nor current index

Instead we rely on internally tracked iterator.

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

* aux/matlab:
  minor, simplify matlab handle layout again, don't store nticks nor current index
  minor, take number of ticks from ute_nticks() directly in matlab's ute_nticks
  minor, use programmatic ute_iter() to provide matlab's ute_tick
Merge branch 'next'

* next:
  minor, simplify matlab handle layout again, don't store nticks nor current index
  minor, take number of ticks from ute_nticks() directly in matlab's ute_nticks
  minor, use programmatic ute_iter() to provide matlab's ute_tick
  minor, use slots in utectx structure to keep track of iter state instead of static globals