Rename
Fix bug where background update_series() doesn't flush cache
Rename variable 'chapters_updated' to 'chapters_added'

The previous name was misleading a bit.
Fix bug where new chapters are not added in some cases
Make a access log for each request
Update test cases
Import app directly
Add test cases for naver_url
Remove unused imports
Make mock_obj return a Mock object without a spec
Add a test case for as_naver_time_zone
Wrap a long line
Add test cases for inner_html by converting its doctest
Add a test case for get_public_ip()