4.3.0

Major Changes

• Template molecule -s default with dummy docker driver
• Support CentOS/RHEL 8
• Support Ubuntu 20.04
• Remove Ubuntu 16.04 support
• Upgrade minimal Molecule support to 3.0.2
• Migrate role name to lowercase or underline
• Migrate group name to lowercase or underline
• Migrate molecule group_vars to file
• Split role as kube_master and kube_node
• Support both docker and cri_o
• Support both LocalEtcd and ExternalEtcd