Ticket 47756 - Improve import logging and abort processing
Description: When importing a heavily nested LDIF file, the numsobordinates
and ancestorID creation can take a very long time. The current
logging doesn't state that it started working on this areas, and
it can appear that the import is hung, when in fact is it working.
Also, there are a few places, when an error occurs(e.g. out of diskspace)
where the the import will hang, and aborting the import doesn't work,
and shutting the server down will also hang, and then it has to be killed.
Added the missing "abort" checks in some loops, and also improved
the import logging(progress stats, etc) for numbsubordinates and
ancestorid creation.
https://fedorahosted.org/389/ticket/47756
Revewed by: nhosoi(Thanks!)