Add support for RHEL/OEL/CentOS 7

[LightAxe]

Requesting support for RHEL/OEL/CentOS 7. RHEL7 was released over two years ago and has become the target for many new systems.

[cardil]

Thanks for the issue. In monday I will try (or maybe @Cosaquee) to determine if your request could be compatible with RHEL 6. For now I think it might be. If so, we could plan this issue before 2.0

Update: changes from my branch to support wildfly 10 also partially fix this issue . Puppet code for managing systemd must be written to fully support systemd os's

https://github.com/coi-gov-pl/puppet-jboss/compare/feature/support-wfly-10

[LightAxe]

Please don't rush to add support on my account; I won't be able to use this module until it supports Puppet 4.2.