This commit adds 'files' table. This files table has coverage_id
column as a foreign key for the coverages table. And this commit also
adds a release note for it.
Change-Id: I8998a79a1ba79bbdab1cd79810cc85bcbccbe7d8
This commit introduces pip-check-reqs task to tox.ini. We should avoid
inconsistency between (test-)requirements.txt and actual source code.
Change-Id: I9d734cdbc1c1fb3283835890b8132e54a7b757d7
Masayuki Igawa