Specify the nginx log file for jenkins service.

Before this commit, the nginx log file for jenkins is: access.log.
This is not intuitive.

So, after this commit, the log file is: jenkins.log.

This commit fixes #222.
Merge branch 'id/222' into dev
Tuning my.cnf.

In order to avoid swapping,
tuning my.cnf.

This commit fixes #221.
Merge branch 'id/221' into dev
Deploy the .ssh/config file.

Enables the following connection:

- bitbucket
- GitHub

This commit refs #220.
Deploy the SSH secret keys to ~/.ssh.

This commit refs #220.
Initial commit for adding tech cookbook.

This commit refs #220.
Add dependency on nginx.

tech blog depends on nginx,
so add dependency on nginx.

This commit refs #220.
Add `tech` user.

Add `tech` user, whose sole role is to manage the tech blog data.

This commit refs #220.
Add SSH authorized_keys to ~/.ssh.

authorized_keys includes:

- Chef public key

This commit refs #220.
Make target directory for tech blog data.

1. Make directory: ~/tech/public.
2. Link /var/www/nginx-default/domain/tech to ~/tech/public.

This commit refs #220.
Deploy the nginx configuration & make the site public.

This commit fixes #220.
Merge branch 'id/220' into dev
Change the Redmine repository URL.

Before, the repository URL is Read-Write permission,
so the authentication is required.
The cause of the test failure is this.

After this commit, the repository URL is Read permission,
so the authentication is not required.

This commit fixes #223.
Merge branch 'id/223' into dev
Make sure that /var/www/nginx-domain directory exists.

This commit fixes #224.
Merge branch 'id/224' into dev
Do not mount `path` as tmpfs.

Inside Docker container (= LXC container),
directly executing `mount` command is not permitted.

To work around this problem,
check whether the environment variable `DOCKER` and
if its length is 0, do not execute `mount` command.

This commit fixes #225.
Merge branch 'id/225' into dev