Include the recipe for monitoring `aptitude` activities.

This commit refs #30.
Install prerequisite gems.

This commit refs #30.
Deploy the configuration file for monitoring /var/log/apt/history.log.

This commit refs #30.
Deploy the configuration file for processing /var/log/apt/history.log.

This commit refs #30.
Merge pull request #30 from kazu634/id/30

cron-aptでUpdateが行われたら通知するようにする