Redundant nn_event::active field removed.

The field was obsoleted by queue items being aware of whether
they are contained in a queue or not so.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Redundant nn_timer::active field removed.

The field was obsoleted by list items being aware of whether
they are contained in a list or not.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
Broken encapsulation between nn_timeout and nn_timer fixed.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>
'active' member from nn_timer and nn_event removed on Windows

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>