Add unicode_literal versions of test_read/write.py
Change test type() == str to isinstance(basestring)
Update io.ascii csv interface to coerce args to str() type
Update CHANGES.rst
Merge pull request #1949 from taldcroft/ascii/uni-lit

Allow passing unicode delimiters in io.ascii read and write
Test code with both unicode_literals and without
Allow testing packages that don't have a doc section.
First pass at resolving issues when testing with/without unicode_literals
Remove redundant test_*_unicode.py files