Added JSON format result log to crawlering history.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Added list display at Django admin.

Signed-off-by: Kouhei Maeda <mkouhei@palmtb.net>
Change python-coveralls to coveralls.

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