Made simple.xlsx test a little more strict.
New sample data large.xlsx which is prohibitively slow in openpyxl. New tests to verify the dimensions of each sheet
Made the tests stricter still, doing type checking on floats extracted from xls and xlsx
Replaced XLSX usage with XLS. Added a DeprecationWarning and backwards-compatibility test for the benefit of people who use XLSXTableSet directly.
gitignore file
Put openpyxl back into setup.py for backwards compatibility
Replaced assert_is_instance(..) with assert_true(isinstance(..)) for Python 2.6 compatibility
Now we use assert_is_instance on python 2.7 and fake it on 2.6
Completely removed openpyxl and linked XLSXTableSet directly to XLSTableSet
Merge branch 'master' into 83-remove-openpyxl
[#83] Update changelog