Add the changes in 0.4.3 into CHANGES.md

[HyukjinKwon]

This PR adds a note for 0.4.3 - #157

[codecov-io]

Codecov Report

Merging #158 into master will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@## master #158 +/- ##
=======================================
Coverage 83.91% 83.91% =======================================
Files 1 1 Lines 541 541 Branches 98 98 =======================================
Hits 454 454 Misses 63 63 Partials 24 24

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