Puppet 3 requires ruby-hiera.

This is not installed as an apt-get dependency
Explicitally convert string to int
Update path of md5 for puppet3
Change code that generates crontab entries to work with puppet 3
Update DTG modules to not use deprecated puppet 2 variables
Update path for MD5 in cron_minute
Update exim module's variable access to use non-deprecated semantics in v3