Specify the user/group of application directory.

This commit refs #79.
Deploy the `Nginx` configuration file.

This commit refs #79.
Enable `WebApp::Calendar` service.

This commit refs #79.
change mode of app directory.

This commit refs #79.
Create the log storage directory.

This commit refs #79.
Change the group of the app directory from `webapp` to `www-data`.

This commit refs #79.
Deploy the logrotate configuration file for `gcal` webapp.

This commit refs #79.