internal: added NewInheritanceMatcher

Includes reference to CLDR documentation discussing the matching.

Change-Id: I7480fe6ef09d3ba9a7848511d4d83d0c06cdc6e1
Reviewed-on: https://go-review.googlesource.com/13075
Reviewed-by: Nigel Tao <nigeltao@golang.org>
3 files changed