0.2.0: Add break cursors (ICU break iterators).

This release adds new types to represent ICU's various break iterators (which we call "cursors"). There is a concrete type for each kind of cursor (Character, Line, RuleBased, Sentence, and Word), which use strongly typed rule status values instead of plain integers.

0.1.3: Update icu4c dependency to 1.0.1.

Fixes the missing usearch.h dependency by updating to the correct version of icu4c, which wasn't caught when working in Xcode.