Revert "Merge pull request #167 from halfcrazy/add_unicode_support"
Revert "Merge pull request #167 from halfcrazy/add_unicode_support"

This reverts commit 144b9d6880d35d53b29baf996d61511ec85a5092, reversing
changes made to 324b65b3ec1617e52c2018a70aea8abd7c425f72.

The feature is not really useful since no people want non-english
chars in imported module name.

dan-blanchard/thriftpy,dan-blanchard/thriftpy