Revert "Fix https://github.com/e-dard/flask-s3/issues/17"

This reverts commit 4e9b98df3fcba5a18a311603d5d02726bb8e47e5.
Pep8 fix: trim lines to 80 symbols in each line
Revert using unittest
WIP
Change setup.py
Revert from nose2 to nose