Prevent duplicate zone entries (3)

Stop district statisticians adding duplicate zones under hierarchy using slightly different names (e.g. Solwezi and Solwezi Central) because they can’t easily find the first entry. This will be achieved by creating a system that picks up all the names that are similar and serves the user with a note that tells the user that similar zones already exist, and are they sure that they want to add a new zone with a similar name? 


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