Install `omnibus_updater` cookbook to update chef client.

This commit refs #113.
Modify `Berksfile` to follow the behaviour change of `berkshelf` due to its version up.

This commit refs #113.
Include `omnibus_updater` cookbook to the base role.

This commit refs #113.
Change the cookbook name from `chef-td-agent` to `td-agent`

This commit refs #113.
Suppress the restarting `Chef client`.

This commit refs #113.
Exclude the `sensu::dashboard_service` recipe.

This commit refs #113.
Merge pull request #113 from kazu634/id/113

Chefのアップデートを行う