Install python-demjson package in order to test the json format validity.

  This fixes #36.
Merge branch 'id/36' into dev
Check the json file format validity when testing.

  Chef solo fails often because the json file format is invalid.
  Before commiting, check the json file format validity.

  This commit fixes #39.
Merge branch 'id/39' into dev
Output the logs regarding Redmine to /var/log/redmine.access.log.

  This commit enables the log analysis easy,
  because the logs about Redmine is output to the /var/log/redmine.access.log.

  (Currently all the nginx logs is output to the /var/log/access.log)

  This commit fixes #14.
Merge branch 'id/14' into dev
Continue Unit testing, even if jsonlint does not exist.

This commit fixes #41.
Merge branch 'id/41' into dev
Merge branch 'dev'