def install
      return false unless install? quiet: !(logger.level == Logger::DEBUG)

      UNIT_TYPES.each do |type|
        units[type.to_s.pluralize.to_sym].each do |unit|
          return nil unless install_unit(unit, type)
        end
      end
      true
    end
def install
      return false unless install? quiet: !(logger.level == Logger::DEBUG)

      UNIT_TYPES.each do |type|
        units[type.to_s.pluralize.to_sym].each do |unit|
          return nil unless install_unit(unit, type)
        end
      end
      true
    end
Installs all units from the manifest.
 @return [Boolean, nil] if units were installed or nil if fails mid-install