4.0.0

• added support for RedHat-based systems
• separated Debian from Redhat variables
• oracle_java_default (default:no) replaced by oracle_java_set_default (default:no)
• directory structure changes
  • tasks/os_family/*.yml changed in favor of tasks/{{ ansible_os_family }}/{{ ansible_distribution }}.yml
• added debug task
• role-specific facts now used to set if an installation process is necessary in Debian or RedHat
• fixed build issues related to tox 2.0.1