Fixed dependencies.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Integrated pylint, pychecker to tox.

  * disable PyPy and pychecker.
  * PyPy error is Debian package python-virtualenv bug (#763389).
  * pychecker cannot suppress debian package python-magic.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Added .gitignore.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Removed unused module importing.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Added build_sphinx, upload_docs sections to setup.cfg.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Chagned using hasattr instead of get method.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Added check_file function.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>