Japanese text should use full-width punctuation by default

When typesetting Japanese text, punctuation marks "。、？（）「」…" are usually set to take up the same amount of space as other Japanese characters (full-width characters). Some characters (including punctuation) can be typeset using half-width variants under special circumstances.

Qts default should be full-width.

Steps to reproduce:
1. Run the attached qml file.

Expected results:
Every character takes up the same amount of horizontal space.

Actual results:
All punctuation marks are typeset using half-width variants.

Compare the attached screenshots of qt and TextEdit rendering "日本語、日本語。日本語？日本語！〜（日本語）〜". See also http://en.wikipedia.org/wiki/Japanese_punctuation