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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