Open text files in binary mode
On second thought, that's a bad idea
Encoding fixes in text._text (pattern code)

- Also, use isinstance(s, basestring) instead of type(s) in string_types
Open pattern resources using utf-8 encoding
Fix basic_extractor

Fixes bug where basic_extractor extracted features such that
contains(WORD) was always False
basic_extractor and contains_extractor are now case-sensitive,
i.e. contains(I) is no the same as contains(i)
Update version number to 0.7.1-dev
Fix py3 tests
Fix repr with non-ascii strings
Update changelog
Suppress scikit-learn warning

This is fine, since TextBlob doesn't support Scikitlearn classifiers
Also, bump version to 0.7.1